So in my experience it's just a matter of trying as many as possible and then reacting when you find something you like. The tricky thing about that is that they can be good for different reasons; One guitar may sound really nice for recording, another one may play really nicely and be good for amplified live playing and so on... So just be aware of what you'll be using it for!
For lower end acoustic guitars, I'm continuously impressed with the YAMAHA acoustic guitars. The FG700S is $2-300 and sounds really good, but the models just "above" that one are great too.
If you want to be able to plug in, get an L.R. Baggs M1 sound hole pickup (About $170 I think). You can install it yourself and it sounds way better than most other pickup systems.
Hope this helped you!
Anders