Found this site that lists a bunch of FAQs and tips about NKP:

http://netkarpro.blogspot.ca/2011/09/netkar-pro-faq-and-tips.html

What day/time would work for everyone to setup a race event? It would be fun to get together and do maybe 2 or 3 consecutive medium-length races on various tracks with various cars. I know that about half of the members are in Europe, so it would probably be on a weekend. Afternoon for some of the members, evening for the others.

I just found out that there exists an Assetto Corsa group:

http://v1.steam.hlxgame.cc/groups/AssettoCorsaRC

These guys will most likely play netKar Pro as well. At least until AC comes out. So be sure to join that group as well.