Welcome
Katnip43,
Welcome to the forum and thank you for your service. I, too am familiar with the M-60, 38 (I was in the Air Force, we didn't use 45s) M-79 and, of course, the M-16. Since then I have more experience with 45s and 9mms and others.
Don't discount the utility of sub-lethal measures. A good size can of pepper spray is about the same cost as one box of bullets. Pepper spray on your keychain and in a holster mounted in your car or bedside are good any time, and especially while you are deciding what firearm to get.
You are following in the recent footsteps of another member, Kayla
The thread with the title
Where do I start?
http://www.thefiringline.com/forums/showthread.php?t=370031
is an excellent one for you to read. You will have many of the same questions she had.
When you go to the gun show, you will meet many helpful people and, sadly, many like this one:
Adamant about a .22
http://www.thefiringline.com/forums/showthread.php?t=373798
Go armed with as much information as you can learn between now and then.
I will echo the suggestion to check out the Cornered Cat site. Pax (who moderates forums in The Firing Line) is the author of that web site and is considerate and knowledgeable. Her advice is always sound and well-reasoned. I recommend the site to women and men.
I also second the advice about going to a range that has rental or "loaner" guns. If (as we do here) there are no such ranges, I would advise your first purchase be a .22 rimfire pistol. It will provide good practice and give you something to shoot at the range, where you will find plenty of guns to watch other people shooting. And if your range is anything like my local range, people will be eager to let you admire their (pride and joy) guns and perhaps even shoot a few rounds. I recommend a good affordable but accurate gun like the Ruger Single-Six or Ruger Mark III (or used, II or I). 22 Rimfire ammunition is the most affordable ammunition around (only airgun pellets are cheaper) and you will always have a use for a good 22. But make sure to get something accurate. There are other makes out there, but I like Rugers and they hold their resale value well. You can hardly go wrong with a Ruger Single Six. If you could find a Ruger SP101 in 22, grab it! It is not as accurate as the single six (because of the sights) but they don't make them any more and if you eventually get an SP101 in centerfire (327, 357 or 9mm) you have a matched pair. The Taurus 22 (Model 94 I think) is nice, but the trigger is a little heavy, and the new Smith 10-shot revolver is REALLY nice, but expensive. Colt Woodsman is very good. Etc etc. Get a 22 for practice. You won't regret it.
Private sellers should let you test-fire their guns, and checking out a revolver is not all that hard.
http://www.thefiringline.com/forums/showthread.php?t=57816
My first duty station was at Kirtland/Sandia. But that was decades ago. I'll bet Albuquerque has changed a lot. OK reminisce over.
Good luck, good shopping.
Lost Sheep
Remember, only believe half of what you see and one quarter of what you hear. That goes double for what you get from the internet.
Do your own independent, confirming research when ANYONE gives you new facts on the web.
Also remember, even the idiotic stuff might have a kernel of truth buried in there somewhere.