Copyright Laws

Hello, this is quitem important to me and I hope that somebody is going to read through this andmaybe help me out?

I want to make a gallery, but before I need to know. Can I get sued if I have images of celebs. on my gallery?

Which pics are absolutely forbidden to display? I know a few people who've gotten a warning from Getty images etc. Should I stay away from watermarked photos, or should I stay away from the High Quiality? I never claimed the photos as my own, but they are copyrighted to their respectful owner.

Also, how can I get an image accounts, does it cost? Or do I just make an account for free?

Somebody want to tell me more?

This also has to do with graphics and icons. Can I use the photos for icon/graphic making?

I'm sorry if you feel this is off topic! :( Be kind, it's my first post here!