Where do all the modders/mappers hang out?

[the tackle]

Sorry if this has been brought up earlier, but here goes:

What's the status with modding and map editing? I can't wait to get started, though I read something that went like "once the full SDK gets out.." - is this what we're all waiting for?

And where are all the mappers? All I find is several sites (which may or may not be deutsch) with forums containing about 1-5 posts each, all about things unable to catch my interest (as in dead old or completely irrelevant, mod/map-wise).
This "hammer" utility I've heard of, where's that to be found, and is it a map editor or what?

Oh by the way, anyone know why there's no brass shells ejecting from handgun?

thanks in advance

 

[Snowknight26]

http://collective.valve-erc.com

 

[UKchaos2]

http://www.snarkpit.com/

and

http://www.mapcore.net/

 

[the tackle]

thanks guys!