I have many columns of names. The data is sorted out into the following
columns: First, Last, Address, City, State, Zip.

John Doe 1234 E Street Los Angeles CA 12345
Jane Doe 1234 E Street Los Angeles CA 12345
Bob Smith 4321 Tree Ave Denver CO 54321
Joe Johnson 987 North Lane Philadelphia PA 65432
Sue Johnson 987 North Lane Philadelphia PA 65432
Lisa Johnson 987 North Lane Philadelphia PA 65432

I want to combine John & Jane Doe into one row, Joe, Sue & Lisa Johnson into
one row, etc.

what can I do to look at the addresses, see if they're the same, look at
last names, see if they're the same, then combine first names into one row
with the appropriate last name and address info?

Using Excel 2007 and Tables:
http://www.savefile.com/files/1882423