Its hard to beat a 22 pistol. Ruger 22/45, Browning Buckmark, S&W 422, Beretta Neos, Ruger SR22P, Bersa Thunder 22, all reasonably priced, excellent pistols.
Those questions are pretty pointless because they are like "What kind of car should I buy? or "What kind of woman should I marry? There are many opinions of both the "don't" and the "do" variety, but nothing is solved. Find a friendly gun shop and look at what they have. Get a general idea what you want and will be comfortable with. Then begin to narrow the search down.
Like cars (or wives) you probably won't find everything you want in one model; if you want to haul furniture for a living, you probably won't want a Ferrari; if you race cars for money, forget the moving van.
Take a look at what CDNN Investments has on their website. There should be plenty of options that are within your budget, one I saw the other day was a Sig 220 (45acp) for less than $500. That wasn't the only good deal on there.
cz75 p-01 9mm, Glock 19, S&W 6906, Ruger sr9c. You got plenty of choices at that price if considering used as well. Almost forgot, Sig SP2022, used p225.
Everybody needs at least one 1911, even if it's not what you would carry. If I were thinking SHTF or defense, I might go with a Glock, but otherwise I love the 1911.