All the high-end composite bats are made here in the US. There was a time when Easton had theirs made in China, but due to significant quality issues, that operation was pulled back home. I believe Worth did the same. Louisville Slugger moved their manufacturing to China in 2009, but I couldn't find if or when that has changed. Rip-It, Anderson, Mizuno and other lesser brands are still made there, as are Dudley and Reebok senior bats. I couldn't find where Adidas senior bats are made, but I think they are from China as well. AT10 could correct me on that one.
I did see several places where a majority of the cheaper aluminum bats under $100 are still made out of the country.