gremwood,
There a ton of racing series and leagues you can join.
League of the Americas (LOTA) has racing on Thursday evenings (two GTR leagues, one is unrestricted, one is field balanced with restrictions) and on Monday evenings (random cars/track chosen by the drivers). LOTA normally races at 9:30 PM EST. Comprehensive rule set, very well organized, and a great community.
On Saturdays, there are a number of leagues in which to race. Most are in Europe in their evenings, so you are looking at 2PM EST average start time locally.
Original LFS League (OLFSL) is a good one because it places you in a pool that most closely matches your speed. If you are looking for an open wheel series, check out
Open Wheel Racing League (OWRL), which like OLFSL, puts you in a pool per your speed and you move up as you prove your skill.
A few others that seem pretty active to check out:
Also, keep an eye on the
Leagues and Events section on these forums. You can see discussion forums for most leagues (some are info only as the convos happen off site), and also information on single events that can be a lot of fun.
Regarding the IGTC and MoE...these series you need to be part of a team to get into these series, and they are very tough leagues that attract some of the best racers in LFS. Not to discourage you in looking toward these as a goal...just be informed of the difficulty and requirements.
As you can see, there are a ton of choices. Check into them, see what you think fits you. Just remember that league racing will generally be more serious than pick-up racing, even the organized pick-up racing like CTRA. You get out of league racing what you put into it, so if you are willing to work at it, league racing can be very fun and rewarding.