Which are the snakes which grow 11m long found in America?

Without a better description, it's hard to be species-specific. However - there are relatively few snakes that get to that size. The only one that comes close - is the Reticulated Python (Python reticulatus)

It's natural habitat is South-East Asia, and specimens normally only grow to around 10-20 feet - although it's possible for them to grow to over 28 feet. Any specimens found wild in America have been imported - then discarded by owners when they outgrew their novelty value !