Good news and bad news...

Good news - www.photoshopuser.com
Bad news - you'll need a membership and it's $99

Tutorials galore on any version of subject you'd care to learn, as well as a monthly magazine with tips and tricks, advice, and cool tutorials. Yes, I'm a member.

Otherwise, I'd suggest Getting a few books depending on what version of photomanipulation you want:

"I've Got a Human in My Throat" - the folks at Worth1000.com: (bizarre manipulation)
http://www.amazon.com/Ive-Got-Human-Throat-Delusions/dp/1598630709/ref=sr_1_1?ie=UTF8&s=books&qid=1234237809&sr=1-1

"Welcome to Oz" - Vincent Versace: (elegant and effective manipulation)
http://www.amazon.com/Welcome-Oz-Cinematic-Photography-Photoshop/dp/0321585461/ref=sr_1_1?ie=UTF8&s=books&qid=1234237836&sr=1-1

"Surreal Digital Photography" - Barry Huggins: (back to bizarre!)
http://www.amazon.com/Surreal-Digital-Photography-One-Off/dp/1592003893/ref=pd_bxgy_b_img_c

Hope this helps-
-Lew