Ebay has 2 ways for you to promote yourself and your hobbies and sites!
First, go into My eBay. Use the My World in the center left to customize your basic page with your hobbies, interests and bio. Mention your writings here. This is the page that comes up when someone looks at your name.
Then go into your Preferences and set up your About Me page. This will create a little "me" colored link next to your name. You can put in your photo, bio, favorite links and more!
To give an idea, here's my "me" page -
http://members.ebay.com/ws/eBayISAPI.dll?ViewUserPage&userid=lisajsheaand here's my "My World" page -
http://myworld.ebay.com/lisajshea