Colbalt, as forever_kaos mentioned we can always use new recruits for either side. We have guys that do both German and Allied and they pick which side depending on the numbers that sign up or how they are feeling. So I would suggest pick the side that most appeals to you. You can always do the other side at a later date. If you are interested in more then just airsoft then doing both sides is great because we have some living history events that only Allied can attend. And trust me when I say that some of our living history events are not to be missed. Go on our forum and check out the pics in the AAR section.
Obsolete, the FSSF or 1CanPara would be perfect for you. Yes, the FSSF is a new unit in our group but you always have to start some where. When I started Ontario Airsoft WWII Re-enactors it was just me running around in WWII gear. The nice thing about the FSSF is that you use US uniforms, gear and weapons... which is very easy to get.
Here is a site that lists out the uniform and gear for a basic impression and an advance imppression.
http://www.members.tripod.com/fssflhg/id144.htm
I suggest for both you fellas and anyone else to to join our forum and ask any questions that you might have. The guys are always welling to help and point you in the right direction.