My advice to you is to start sifting through obfuscated posts and figuring out how they work. After you have parsed 4 or 5 of them you should be able to start coming up with some of your own. Thats the joy of Obfuscation... figuring out how to do it well! There are lots of great examples here.
in reply to Lost in a sea of obfuscation...
I've now updated this post with links to many great examples of obfuscation here in the monastery. Enjoy!
Okay, first... its my post, and it wouldn't be right to include my own work in my list of great examples, so here are my posted obfuscations:
Now on to the really good stuff:
Also check out the tutorials from Japhy (japhy's Obfuscation Review) and autark (Unobfuscated obfuscated perl course).