Excel Expert Needed - (not data entry) I need a formula/macro I think :)

Hello, We are looking for someone to help me with 4 spreadsheets contacting 4 brands of cross references from many brands. There are approx 30,000 cross references within these spreadsheets. I need 4 brands of cross references making into one spreadsheet, this finished spreadsheet must contain as many cross references as it finds within 2 columns. I find this hard to explain so I might see if anyone can help me when bidding, on a test :) Many Thanks Tom