Lisa, welcome to the forum and thanks for asking our advice.
Congratulations for going about this in a thinking manner.
If you share with us what your goals are (self-defense, home defense, target shooting, "just because", etc.) and what your intended uses are, we can advise you better. Do you live in an urban, suburban or rural area, for instance. Will you carry it outside the home? etc.
My recommendation is for a 22 rimfire. Below my recommendations list is my reasoning.
semi-automatics:
Ruger Mark I, II or current model III
or Browning Buckmark or
Smith & Wesson Model 41
Revolvers that come immediately to mind are:
Ruger SP101
Ruger Single-Six of Single-10
Smith & Wesson's K-Frame K-22 "Masterpiece" (I had one a while back)
Smith & Wesson 617
Taurus 990 or 94
Here's my reasoning:
1 Practice is important for becoming a good shot. Practice (beyond dry firing) takes ammo. Ammo is cheaper for a 22 than for any other caliber. Example: 22 rimfire costs (around here) $20 - $30 per 500. 500 rounds of 9mm (a very inexpensive round) is at least $100 to $150 per 500.
2 Practice with a round that has almost no recoil makes concentration on sight picture, breathing and trigger control much easier without the distraction of recoil and excessive muzzle blast. You can add those elements later after you have gotten the basics ingrained in your subconscious. If you start out with a hard-recoiling round you are almost certain to develop anticipation (usually characterized by a flinch) which is devilishly hard to cure. Prevention is much easier to, especially while you are learning.
3 Having a good, accurate 22 will put you on the range (if you go to a formal or informal shooting range) where you will get acquainted with other shooters, see their gun handling practices and see their guns. Most gun owners are proud of their hardware and if you exhibit good safety practices, a modicum of shooting skill and a little bit of polite interest, they will very probably let you handle their guns and even send a few rounds downrange. You can get to try out a wide variety of guns that way and collect testimonials from people other than salesmen when you go to a store.
4 Most (accurate) 22 rimfire guns are cheaper to buy than similarly accurate centerfire guns and hold their resale value well.
I also recommend you visit a web site owned by one of the administrators on The Firing Line, "Pax". It is principally written for women new to guns, but most of the information there is EQUALLY applicable to either gender. "New to guns" is "new to guns" whether male or female.
http://www.corneredcat.com/Contents/
Good luck. Thanks for reading.
Lost Sheep