Create a table on sheet1 with headers like: Name (make sure this is the first thing on the row), Address, Phone, etc. On another sheet (sheet2) select a cell, lets say A1, and type the word "Name"; on cell B2 insert a drop down list for the names on the other sheet by clicking on DATA > DATA VALIDATION> ALLOW: list > select the source range which should be the entire column range containing all the names on the first sheet with the table/data. Now you should have a drop down list with all the names and hit OK.
Next: on the same sheet (sheet2) where you have your list created on B2, design how you would like the data to be presented by choosing any cell and typing "addresses," for example, and on the next cell inputing a vlookup formula that will lookup the addess info for the contact name selected on the list. Using the example given so far it would be =vlookup(B2,--on this part go to the sheet where the table is and select the entire table by highlighting all columns with data--,--on this part put the number in which the address info falls in (it will be number 2 if this info is what follows the name on the table--, FALSE): so you will end up with something like =vlookup(B2,'sheets1'!,2,FALSE). And so on, and so on.