Welcome to the site Lizzie, and feel free to ask questions here on G2G if you need help! Also, Laura and Jenny from the Greeters have left messages on your profile, I'm sure either one of them would be happy to help you with any questions you may have!
I will be working on loading up the United States Census records later this year, but may not go much beyond 1850, as that is when individuals began to be reported and the numbers balloon at that point. Perhaps Horace's grand-parents could be found in earlier census records in Indiana or other eastern locations in the US. If they immigrated from Canada or Ireland, then they may be there already.