Prices of backpacking tents vary considerably. Materials and the weight of the tent cause prices to range from under $200 (such as the Kelty Late Start 2) to over $1,000 out the door.
Specialized ultralight tents such as the Hyperlite UltaMid or burly all-weather mountaineering tents are usually the most expensive and are made from very strong and light materials.
Less expensive tents are priced for the beginning or occasional hiker. Expect to spend a third of your budget on a tent, another third on your sleeping bag, and the rest on your cooking supplies, etc.
The amount you are willing to spend depends on your commitment to the sport. Affordable options are a great place to start, as you can then gauge your willingness to invest.