Mike:

What are you looking for in a "Unit"?
Do you have a set of specific requirements/expectations for the group you look to join up with? (Infantry, Cavalry, Artillery)

If you are looking for a high quality Infantry unit that does a great Confederate impression, I'd look at the 9th Texas Red River Battalion...
http://www.9thtexas.org/

Let us know more specifics on this BB, we could be of more help to ya!
Respectfully:

Kevin Dally