Check out this question and answer it if you would.
http://answers.yahoo.com/question/index;_ylt=AjeynS8nBQGNtm5BiqwXTDzsy6IX?qid=20070804080142AAj3nxj
If you don’t know how to change your avatar, here is how:
1. Go Google, type "MLB team, Logo".
Example: "New York Mets, logo"
2. You should be able to see the logo after you hit enter.
3. Choose the logo, Right click and Save as a new file. (*.jpg)
4. Go to your 360 profile.
5. Hit the "My page" tab on the top.
6. Hit "Edit personal photo".
7. Hit "Browse", Select the logo file, and Save it.
8. Set the picture as your primary.
9. Log in to Y!Answer again.
10. There you have it. A new logo!