Pulling data from 2 spreadsheets into new rows

[b19upj]

Hi,

I have 2 spreadsheets.
I want the information contained in the first spreadsheet inserted as new rows in the second spreadsheet where a certain condition is met.
The added complexity to this is the first spreadsheet may have more than one row to add to the second row.
An example is this: Column G contains a 'Grouping Ref'. The first few rows look like this

Grouping Ref 30
30
20
30
30
20
30
30
20
41
41
41
41
41
34
34
35
34
34

<colgroup><col></colgroup><tbody>
</tbody>

On my first spreadsheet column J is 'Grouping Ref'. The first few rows are:
Grouping Ref

30
30
30
31
32
33
33
34
41
41
41
41
41
41
34
34
35
34
34

<colgroup><col></colgroup><tbody>
</tbody>

How can i get the second spreadsheet to look up the first one for a grouping ref match, then add the number of rows in it depending on how many rows are associated with that grouping ref number on the first spreadsheet.
Once it has matched it and added the rows, it would need to replicate the information from the above row which had the matched group ref, but in the last column (L) add the text in column B of the first spreadsheet.

I hope that makes sense.

TIA