There's enough credit linking me to these maps around the web that I'm not likely to end up losing my name on them due to GRRM not crediting me. However I agree that it was a bit odd.
It's extremely surreal seeing these in stores and seeing the reviews, posts and unboxing videos around the web. Personally I've got North of the Wall framed in my living room. It looks great.
It has indeed opened up some interesting options. More about those in due course (and one of the reasons for me being MIA for the last couple of months). Hopefully I'll be around a bit more in the near future!
As for selling the maps - I can't sell them directly but you can pick them up via the affiliate link and I'll get a small cut! http://amzn.to/SkK4oQ