"Slim pickins" is the best way to describe this section. While clean humor sites can be found easily, Purim Torah sites are few and far between. My theory for this is the fact the the best Purim Torah is done by Yeshivish people who are big talmidei chachamim and have a nice sense of humor. these people lack technical skills, and also stay away from the Internet. The people who have technical skills and use the Internet usually aren't Yeshivish. Furthermore, even websites advertising "kosher humor" contain treif jokes The result- a paucity of Purim Torah on the Internet. This is what I could find:
Passover Haggadah for computer programmers
Bernard Schubach's Purim Torah collection
My favorite kosher cartoon strip, The Far Side, gets a Jewish twist! Chopped Liver!
The Josh Lintz Clean Joke Archive
For more clean jokes, search Google for "clean humor". I can't recommend sites just in case they lie about content , but they do have some nice ones there.