check out aerlingushotels.com. it won't give you discounts or anything but it is a good website for finding hotels. it's faster than travelocity, ect and you are able to map location after selecting. like that other cat said, good luck on cheap. I went to Madrid and Barcelona, MAD got a 3 star hotel, $120 a night. typical euro hotel (small), but a great location.
another thing like the one guy mentioned, hostels.com. most offer a "private/ensuite" for around 50-60 dollars a night. i've done it twice, both times I was pretty impressed with the location as well as overall cleanliness of the places I stayed.