How to compare two worksheets and output the results

Scenario (using Excel 2003):
I have two worksheets.
"Sheet1" has 500 entries with the columns Email Address, First Name, Last Name
"Sheet2" has 3000 entries with the columns First Name, Last Name, Buddy Name, IM Platform

Problem:
I need to compare Sheet1 against Sheet2. For every person in Sheet1 that has a matching First Name and Last Name found in Sheet2 copy all instances of their Buddy Name and corresponding IM Platform into new columns. The trick here is that a person may have multiple buddy names for multiple IM Platforms (i.e. AOL, MSN, Yahoo, etc).

Sample Data:
Sheet1 -
[email protected] | Rob | Smith
[email protected] | Rick | Tyler

Sheet2 -
Rob | Smith | HotDog23 | MSN
Rob | Smith | [email protected] | AOL
Rob | Smith | yHot | Yahoo
Rick | Tyler | keyz5 | MSN

etc...

I need to grab all those entries for each user found in Sheet2 and their Buddy Names and IM Platform


I'm not an Excel programmer so I'm at a loss on how to start this. Any and all help would be greatly appreciated.

You can create "joint keys", and use a vlookup, with the caveat that this may result in a lot of "#N/A"'s errors. So in table 1, column 4, create a key for John Smith MSN, as "=A2&B2&"MSN". In table 2, column 5 create the same key, "=A2&B2&D2". Column 6 would be "=C2. Then, back in table 1, do a vlookup as, "=vlookup(C2,'Sheet2!e2:f4000,2,false). You will have to replicate one column for each of the IM types (MSN, Yahoo, AOL, etc.), and the same with the columns. Good luck.