Taz, odds are you can find some local reenactors near you. I actually saw a couple serious guys at at con just before Halloween. I also saw in the paper that there were some professionals at a local history museum recently (answering questions in costume for Independence Day).
Aside from that, there are more generic resources online available for reenactors: How to lace up your gaiters / leggings, sample documents, how to interact with the public, how dog tag data was formatted, etc. Also rough guides on what kind of uniform to buy (makers, sizing, color, etc), when you should buy the nice stuff, and when it's OK to go for the cheaper stuff.
Now that I think about it, I think one of my dad's friends did US Civil War (1861-65) reenactment.