Welcome aboard.
Just pick out a title that interests you the most.
You will not have any trouble finding any PBEM opponents over here!
Also, don't forget to check out Task Force Echo-4
http://tfe4.wordpress.com/
It is a one-stop-shop with a ton of 3rd party scenarios, unit art, map/graphics, etc. If you look around, you will find that there are several 3rd party scenarios found for the following games: Eagles Strike (ES), Pacific War (PW), Tour of Duty (TOD), and Vietnam (NAM).
Even though Red Victory (RV) has no 3rd party scenarios shown on TF-Echo4, it is the newest WWII Squad Battle game to be released, and it has been popular in PBEM ladder games. I believe it will be the next title that will be used in the next Squad Battles tournament.
BTW, another good place for AOTR and RV 3rd party graphics is IronxMods
http://ironxmods.wordpress.com/
Any questions? If so, feel free to ask.
Good Luck!