Pix

Well werent you already a member a long time ago? lol. you can however choose from one of the premade avatrs. just go to the UCP and in there it should say edit avatar somewhere.

You cant have a custom avatar without a membership. & to change your gamertag just go to "about me" and change it there. to change your website name you need to request one through the link in your UCP. its towards the bottom.