Hey guys.
300dpi is a forum for all the graphic makers out there. It has many contests (blends,icons,colorizations,add effects etc...), and is a perfect place to improve your graphic skills! It has a Tutorial section where you can try new and wonderful things; for example you can learn how to make this piece
The only requirement is to have eaither Photoshop or any other graphic programme!
You also can create a gallery with all of your art, and in a very short period you'll be sorted into one of the groups.
It has many more options i didn't count, but i won't spoil everything, have a look at it by yourself!
The link