try this idea
in Main Page this is your data
<b>Excel 2007</b><table cellpadding="2.5px" rules="all" style=";background-color: #FFFFFF;border: 1px solid;border-collapse: collapse; border-color: #A6AAB6"><colgroup><col width="25px" style="background-color: #E0E0F0" /><col /><col /><col /></colgroup><thead><tr style=" background-color: #E0E0F0;text-align: center;color: #161120"><th></th><th>A</th><th>B</th><th>C</th></tr></thead><tbody><tr ><td style="color: #161120;text-align: center;">1</td><td style=";">Item</td><td style=";">Site</td><td style=";">Quantity</td></tr><tr ><td style="color: #161120;text-align: center;">2</td><td style=";">Concrete</td><td style=";">A</td><td style="text-align: right;;">564</td></tr><tr ><td style="color: #161120;text-align: center;">3</td><td style=";">Block</td><td style=";">B</td><td style="text-align: right;;">503</td></tr><tr ><td style="color: #161120;text-align: center;">4</td><td style=";">Scaffold</td><td style=";">A</td><td style="text-align: right;;">171</td></tr><tr ><td style="color: #161120;text-align: center;">5</td><td style=";">Roof</td><td style=";">A</td><td style="text-align: right;;">120</td></tr><tr ><td style="color: #161120;text-align: center;">6</td><td style=";">Concrete</td><td style=";">B</td><td style="text-align: right;;">960</td></tr><tr ><td style="color: #161120;text-align: center;">7</td><td style=";">Block</td><td style=";">B</td><td style="text-align: right;;">153</td></tr><tr ><td style="color: #161120;text-align: center;">8</td><td style=";">Scaffold</td><td style=";">C</td><td style="text-align: right;;">381</td></tr><tr ><td style="color: #161120;text-align: center;">9</td><td style=";">Roof</td><td style=";">C</td><td style="text-align: right;;">909</td></tr><tr ><td style="color: #161120;text-align: center;">10</td><td style=";">Concrete</td><td style=";">C</td><td style="text-align: right;;">881</td></tr><tr ><td style="color: #161120;text-align: center;">11</td><td style=";">Block</td><td style=";">A</td><td style="text-align: right;;">62</td></tr><tr ><td style="color: #161120;text-align: center;">12</td><td style=";">Scaffold</td><td style=";">A</td><td style="text-align: right;;">945</td></tr><tr ><td style="color: #161120;text-align: center;">13</td><td style=";">Roof</td><td style=";">A</td><td style="text-align: right;;">696</td></tr><tr ><td style="color: #161120;text-align: center;">14</td><td style=";">Concrete</td><td style=";">B</td><td style="text-align: right;;">639</td></tr><tr ><td style="color: #161120;text-align: center;">15</td><td style=";">Block</td><td style=";">A</td><td style="text-align: right;;">270</td></tr><tr ><td style="color: #161120;text-align: center;">16</td><td style=";">Scaffold</td><td style=";">A</td><td style="text-align: right;;">63</td></tr><tr ><td style="color: #161120;text-align: center;">17</td><td style=";">Roof</td><td style=";">B</td><td style="text-align: right;;">161</td></tr><tr ><td style="color: #161120;text-align: center;">18</td><td style=";">Concrete</td><td style=";">B</td><td style="text-align: right;;">810</td></tr><tr ><td style="color: #161120;text-align: center;">19</td><td style=";">Block</td><td style=";">C</td><td style="text-align: right;;">491</td></tr><tr ><td style="color: #161120;text-align: center;">20</td><td style=";">Scaffold</td><td style=";">C</td><td style="text-align: right;;">868</td></tr><tr ><td style="color: #161120;text-align: center;">21</td><td style=";">Roof</td><td style=";">C</td><td style="text-align: right;;">275</td></tr><tr ><td style="color: #161120;text-align: center;">22</td><td style=";">Concrete</td><td style=";">A</td><td style="text-align: right;;">670</td></tr><tr ><td style="color: #161120;text-align: center;">23</td><td style=";">Block</td><td style=";">A</td><td style="text-align: right;;">888</td></tr><tr ><td style="color: #161120;text-align: center;">24</td><td style=";">Scaffold</td><td style=";">A</td><td style="text-align: right;;">186</td></tr></tbody></table><p style="width:2.4em;font-weight:bold;margin:0;padding:0.2em 0.6em 0.2em 0.5em;border: 1px solid #A6AAB6;border-top:none;text-align: center;background-color: #E0E0F0;color: #161120">Main</p><br /><br />
and in Report Sheet
in A2 you have Drop down List with items name
<b>Excel 2007</b><table cellpadding="2.5px" rules="all" style=";background-color: #FFFFFF;border: 1px solid;border-collapse: collapse; border-color: #A6AAB6"><colgroup><col width="25px" style="background-color: #E0E0F0" /><col /><col /><col /></colgroup><thead><tr style=" background-color: #E0E0F0;text-align: center;color: #161120"><th></th><th>A</th><th>B</th><th>C</th></tr></thead><tbody><tr ><td style="color: #161120;text-align: center;">1</td><td style=";">Item </td><td style="text-align: right;;"></td><td style="text-align: right;;"></td></tr><tr ><td style="color: #161120;text-align: center;">2</td><td style=";">Block</td><td style="text-align: right;;"></td><td style="text-align: right;;"></td></tr><tr ><td style="color: #161120;text-align: center;">3</td><td style="text-align: right;;"></td><td style="text-align: right;;"></td><td style="text-align: right;;"></td></tr><tr ><td style="color: #161120;text-align: center;">4</td><td style="text-align: right;;"></td><td style="text-align: right;;"></td><td style="text-align: right;;"></td></tr><tr ><td style="color: #161120;text-align: center;">5</td><td style=";">Item</td><td style=";">Site</td><td style=";">Quantity</td></tr><tr ><td style="color: #161120;text-align: center;">6</td><td style=";">Block</td><td style=";">B</td><td style="text-align: right;;">503</td></tr><tr ><td style="color: #161120;text-align: center;">7</td><td style=";">Block</td><td style=";">B</td><td style="text-align: right;;">153</td></tr><tr ><td style="color: #161120;text-align: center;">8</td><td style=";">Block</td><td style=";">A</td><td style="text-align: right;;">62</td></tr><tr ><td style="color: #161120;text-align: center;">9</td><td style=";">Block</td><td style=";">A</td><td style="text-align: right;;">270</td></tr><tr ><td style="color: #161120;text-align: center;">10</td><td style=";">Block</td><td style=";">C</td><td style="text-align: right;;">491</td></tr><tr ><td style="color: #161120;text-align: center;">11</td><td style=";">Block</td><td style=";">A</td><td style="text-align: right;;">888</td></tr><tr ><td style="color: #161120;text-align: center;">12</td><td style=";"></td><td style=";"></td><td style=";"></td></tr><tr ><td style="color: #161120;text-align: center;">13</td><td style=";"></td><td style=";"></td><td style=";"></td></tr><tr ><td style="color: #161120;text-align: center;">14</td><td style=";"></td><td style=";"></td><td style=";"></td></tr><tr ><td style="color: #161120;text-align: center;">15</td><td style=";"></td><td style=";"></td><td style=";"></td></tr><tr ><td style="color: #161120;text-align: center;">16</td><td style=";"></td><td style=";"></td><td style=";"></td></tr><tr ><td style="color: #161120;text-align: center;">17</td><td style=";"></td><td style=";"></td><td style=";"></td></tr><tr ><td style="color: #161120;text-align: center;">18</td><td style=";"></td><td style=";"></td><td style=";"></td></tr></tbody></table><p style="width:3.6em;font-weight:bold;margin:0;padding:0.2em 0.6em 0.2em 0.5em;border: 1px solid #A6AAB6;border-top:none;text-align: center;background-color: #E0E0F0;color: #161120">Report</p><br /><br /><table width="85%" cellpadding="2.5px" rules="all" style=";border: 2px solid black;border-collapse:collapse;padding: 0.4em;background-color: #FFFFFF" ><tr><td style="padding:6px" ><b>Array Formulas</b><table cellpadding="2.5px" width="100%" rules="all" style="border: 1px solid;text-align:center;background-color: #FFFFFF;border-collapse: collapse; border-color: #A6AAB6"><thead><tr style=" background-color: #E0E0F0;color: #161120"><th width="10px">Cell</th><th style="text-align:left;padding-left:5px;">Formula</th></tr></thead><tbody><tr><th width="10px" style=" background-color: #E0E0F0;color: #161120">A6</th><td style="text-align:left">{=IFERROR(<font color="Blue">INDEX(<font color="Red">Main!A$2:A$24,SMALL(<font color="Green">IF(<font color="Purple">Main!$A$2:$A$24=$A$2,ROW(<font color="Teal">Main!$A$2:$A$24</font>)-ROW(<font color="Teal">Main!$A$2</font>)+1</font>),ROW(<font color="Purple">1:1</font>)</font>)</font>),""</font>)}</td></tr></tbody></table><b>Entered with Ctrl+Shift+Enter.</b> If entered correctly, Excel will surround with curly braces {}.
<b>Note: Do not try and enter the {} manually yourself</b></td></tr></table><br />
HTH