Info Sites

Mark's Five in a row games
A great windows computer opponent, tutorial for beginners, tournament info and lots of good links!
Wikipedia entry for Pente
Gotta love Wikipedia
Pente.homestead.com
Pente tournaments area, hoping to get live tourneys going!
BoardGameGeek - Pente
Some info, pictures, sites about Pente
PenteWorld - Scott's guide to Pente®
Has some great pente puzzles!
The Renju International Federation
This has some info about pente.
A page about Pente
Another good Pente site with various info.
Solution to Gomoku
The mathematical proof to Gomoku.
Renju/Gomoku/Pente links at about.com

Online Places to Play
Though why you'd want to play anywhere else is beyond me.

Pente.net - Turn-based
Popular site.
BrainKing - Turn-based
Pretty good Pente playing site.
Kurnik.pl - Poland Real-time games
Haven't played there much but they have live tournaments which is cool.
ItsYourTurn.com - Turn-based 
More popular for Pente a few years ago, but a decent site.
Richard's PBeM Server
Play by email site, lots of games.

If you know of any other pente links please let me know.