Seriously, just give one of these rides a shot.
http://www.fatkats.org/club_rides.htm
The Wednesday and Saturday rides are the least 'elitest', but even the most hardcore ride the main issue is safety and being comfortable with the other people around you. If you're riding in a paceline (which is probably the only way you'll do a comfortable 20-22mph) then you need to trust the people you are riding with -- and that takes time to develop.
Enjoy the summer!