What are the stats on the percentage of American households that actually have in-home internet access?

I just read another Fluther question asking why phone books are still distributed. There was some discussion about using the internet to access phone numbers, and there was debate as to how available internet access is to all.

A lot of Americans (all? most?) who don’t have home internet have internet available from their local libraries, but I wonder what the true stats are as to how many have internet access from home?