Escort ZX2 won't start after new battery

I have a '98 escort zx2 with about 130,000 miles on it. About two months ago if I sat in the car and listened to the radio for 10 minutes while a friend ran in a store, the car would not start when they came out. This got worse and worse until finally I replaced the battery. I drove approximately 20 miles with the new battery and now it won't start again. Does this mean that the alternator isn't charging the battery? If it isn't turning over does that make a difference? Assuming that the alternator is the problem, can you give me a rough estimate on the cost of replacing the alternator, an allignment, two tires, and new brake pads? I live in a college town and while the local mechanics assume that mom and dad pay for everything, that is not my case and I'd like to have a rough idea of cost in my mind before I take the car to anyone. Thanks!