The US Census 1790 - 1930 is available for free at the following website:
I haven't examined the entire site, so I'm not sure if the records for every state/territory have been completely converted to a digital format, but my understanding is that the project is expected to be completed within the next 6 months, so if you don't find your records now, you should be able to by March, at the latest.
This is a fabulous blessing—up until this point everyone either had to go blind examining microfilm/fiche at the library, or pay to access this via a subscription service (like Ancestry). Now you can do your searching at home! The census is a fantastic place to get very valuable information about your family—birth places and years, immigration dates, occupation, children that you didn't know existed because they died young . . .
So get started!