So with Priceline you pick an area of the city, pick which rating (3 star, 4 star, etc) and enter how much you want to pay. If you win its going to charge your credit card, if not you can bid on a different star hotel or come back later. I think they only let you bid on same thing every 24 or 48 hours.
Hotiwre will list the hotel amenities, general area location, and some info. it will give you a price and you can buy the hotel stay at that price.
Both these sites come in handy for maybe a last minute trip, or if you don't care what kind of room or bed you have. I have gotten rooms for as much as $90 off regular price.
need more help and tips...one of my new favorite sites.
this site can help a lot. For hotwire it can usually help you narrow down to with one or two hotels.
It can also give you lots of great tips and you can see what others have paid and gotten for hotels.
And don't forget, they do flights, rental cars, vacations and more!