Brown, Wilson, Nighthawk, and Baer are all semi-custom. They offer different configurations of a limited number of platforms. Full on custom are outfits like Heirloom Precision, Harrison Custom, Severns Custom, etc. These guys will start with any gun and use any part or perform any customization you ask. For a full custom, you can spend $5K and wait 2 years. Baers are about $1,800 and currently have a wait time of around a year, but there are dealers who have them and used ones available. The production guns can be had for as little as $600.
The best value depends on what you are looking for. In the Semi-custom category, I like Baer and Dan Wesson. For a production gun, Hilton Yam recommends the S&W E-Series with a few mods:
10-8 Performance: S&W E Series, Detailed Review
A lot of people like the STI Trojan in the production category. You can't go wrong with Brown, Wilson, or Nighthawk, either, but all of these cost more than Baer and Wesson.
My dad told me he wanted to get a a pistol and I asked him what he wanted to spend. He said he wanted a value. I asked him again what he wanted to spend. I ended up getting him an M&P45. I love 1911's. You will never part me from my Baer, but the value is really in the plastic guns. You can't cast or machine cheaper than you can mold plastic.