Enter guitar in the filter box and set the refresh for say 3 years and see what you get. Some don't have guitar in the thread title but if you go through some of the many you find there, you'll find links to most of the others.
Good brands with inexpensive models: Martin, Larrivee, Guild, Yamaha, Seagull, Takemine(Jasmine), Taylor, Alvarez, Epiphone...Also check out Blue Ridge Guitars...lotsa' bang for the buck, really excellent.