I love Picnik photo editing website! You can actually use most of the editing tools for free and if you wanna be extra fancy you can upgrade for about $25/year1 I thought it was a pretty good deal. I'm just getting my feet wet in the DSLR world and photo editing arena so as a beginner it's great to learn with. I like that it has little bubbles that pop up to tell you how the different applications effect your photo.
If you don't all ready use Picnik, go over and check them out! It's pretty awesome!