On crediting I always credit everything because I think it's the right thing to do. Where not otherwise stated, what I post and use is made by ME, so please, avoid using my icons without asking. About the ones that I did not make, you just have to credit the right maker. Thanks. The same is valid for any piece of art I may share on my journal. This includes TUMBLR reposting.
Also, there are chances that I have NO IDEA who to credit for a picture (see my SFL banner, which I edited but obviously isn't mine). If you know the original creator, I would be very grateful if you spent some seconds to tell me so I can give proper credit.
For the list of credits (for art, textures, brushes and so on), please go to the dedicated post (always updated) HERE.
Eventual photographic references credits will be indicated under the finished work.