|Dookyweb||Mad Men||Face Your Manga|
Below is where they come from. I don't know how other people learn about them first. But this is how you get them.
I don't have TekTek illustrated here, but it's a fun anime-oriented tool to create a full-body chiba figurine of yourself, as realistic or outlandish as you'd like to create it. Anime.Mypic is for the serious avatar consumer: it's not a free service and it's not cheap, but the end-product is a one-of-a-kind piece of art unlike anything else out there.
P.S. Yes, I've heard of Zwinky. No, I do not recommend them at all.