Avguste, you have the first requirement to get your own avatar. You have to be subscribed. The second requirement is for you to email it in. There is the thread in Sleuth Talk called Avatar News. I have rummaged through it and found Secret Squirrels post where he gives the email address. Just follow this link, and scroll down to read what the squirrel says. :D
And No there is not a link in City hall anymore as the main post states. That feature was removed. But Secret Squirrel does give the email address out in the post several times.