Another good site for free stock photos is Free Pixels

Take a look!!!
Bunch of stock photo links.

http://www.masternewmedia.org/news/2...ree_images.htm

Some of them need registration, some not, but it's worth to look.

Are any of these sites the kind where we can sell our own photos or are they all just to buy from?

Loads of stockphoto resources here:
http://www.bluevertigo.com.ar/bluevertigo.htm

I use istockphoto, stock xchange, dreamstime, fotolia, and bigstockphoto.

Here's another site, it's still growing though: http://www.adigitaldreamer.com/gallery/index.php

I have always wondered how stock photo sites control the distribution of their photos? If someone chooses to download the photo (after paying for it) and shares it with many friends then wouldn't the owner of the stock photo lose revenue?

Yes, and you would be in violation of the terms and conditions for the usage of that photo. If you are caught, you CAN be prosecuted and don't think it doesn't happen.

I use http://morguefile.com. They are free and anyone can use their photos. All they ask is that you notify the original author telling them where you used the photo.

I have notified several authors and they were all happy that I used their photos. Plus, it gave me one more visitor to my site!

Geez, thank you guys for posting so many links like these. I personally use www.sxc.hu and www.gettyimages.com but seeing that there are so many alternatives definitely makes me happy

Stock Photography by FeaturePics

70% comission

the only one i new was bigfoto.com lol

I personally use Fotolia.com. Only a dollar per image.