you google it like this "1.e4 e5 2.f4" in the search box and analyse the games
Gambit info online??

The forums at http://chesspub.com have great opening analysis in general, also some on gambits. But be very careful when posting there, most of the posters are 2000+, some IMs and GMs are around, and they have little patience. Come armed with concrete analysis and look to see if your question has already been discussed first. Or just read =)
But, e.g., the thread with the summary of all the king's gambit 1.e4 e5 2.f4 exf4 3.Nf3 stuff that has been posted there ( http://www.chesspub.com/cgi-bin/yabb2/YaBB.pl?num=1217111507 ) is pure gold. Very high level analysis, better than most books.
chesspub.com is the forum of http://www.chesspublishing.com , the web's #1 opening theory site.

Wow. That site is off the chain. I can't believe I've never been there before. Recently I decided to fight 1.d4 d5 with 2.e4, the BDG. This site is packed full of info. Thanks!
Where does everyone get their favorite Gambit related info? I personally research unorthodox gambits at Chessville.com. Mainly Clyde Nakamura's gambits. I also find many interesting Gambits at the Unorthodox Chess Openings yahoo group. Oh.. and Wikipedia also has some interesting articles on Gambits.
Where do you find your info?