from the Site Map at the bottom of this page, you will find lots of information about Selling and Photos...

http://pages.ebay.com.au/help/sell/pictures.html

is an example.  Look around the Site Map before you start

make sure you are registered as a Seller

make sure you have your c/card on file to pay your Seller fees

make sure you update your Paypal account to premium or business to accept payments from your buyers.

goodluck