You should just go on a tutorial rampage for awhile until you get the basic techniques down...extracting, blending, adding effects, optimizing, layer masking (goes with blending but deserves one of its own...), and finally, layers and their styles...
Once you have those basic concepts, you can download some nice brushes of your choice and some useful filters and maybe patterns and...basically a bunch of downloading...
After that, I suggest you start taking part in the challenges and contests in PST (
www.photoshoptechniques.com) and learning from them and Battleforums's seksi gosu people
That's where I am right now...and thats what I went through...
So good lucko bucko...
^I know its tempting but DONT QUOTE ME ON THAT