Sam P.
Pony Express and Delmonico gave such good answers that I don't know if I can really add anything...but I'll try
AZSA started as a bunch of IPSC shooters that had some Thompsons at home and came up with a way to play with them, similarly to the SASS started. I know you have guns that will work. The Thompson and the 1911 are the most used firearms, but I've seen Sumi's (sp?), bren's and lots of lever guns. My striker uses his '73, his Schofield and his pump Marlin 19 though he'd be better off using my 1911 or my S&W Model 5. At Byers you have to shoot pistol caliber rifles but can use jacketed bullets and no full auto. Some places allow full auto. (I will but only if you let me put a few rounds through it
) The reason I waited so long to announce the match was that I wanted to make sure it was ok with the powers that be if I didn't run it exactly the way the matches I've attended at Byers were ran. I'm planning on using mostly steel targets with a few cardboard IPSC targets thrown in.
As far as clothes go I wear a pair of bibs, a Henley or a chambray shirt and a beat up old felt hat or a newsboy cap. I've seen everything from cowboy clothes to a 1930's State Patrol to double breasted, pinstriped suits with fedora's Think The Untouchables, Bonnie & Clyde, Legend's of the Fall or You Know My Name.
Don't be afraid to visit the Zoot Shooters forum and ask questions.
http://www.cascity.com/forumhall/index.php/board,108.0.html They're a friendly bunch. There's a thread called "For New AZSA Zoot Shooters" which contains the answers to questions I asked before I attended my first match.
http://www.cascity.com/forumhall/index.php/topic,44871.0.html I was one of the earliest members (#16L) but had never been able to attend a match until 2 years ago.
Here's some video from last fall in Byres
[youtube]http://www.youtube.com/watch?v=J6f09huxq70[/youtube]