OK, it's VERY informal. It's going to start as a online community, all contact will be done by email (keep all costs down), spread by word of mouth - just to get it going.
If it actually takes off, and I want to make it an "ACTUAL" Alumni Club, I'll go the Nationals route. I have read all the documentation that Nationals has for Clubs. Informal is the way to go at the beginning. Then I can do all the documentation with them, to get it mentioned in the Delta, and linked on the sigmanu.org site.