Of course there's Orbitz and Travelocity.
And we can't forget about Expedia and the new kid on the block: Kayak.
There are countless other online travel sites.
Aside from this, one can always pick up the phone and ask. But here's one other tool: if you're going to be in an area for close to a week, ask for their weekly rates. You'd be surprised how deep a discount you may land.