I donīt think that you can get a JetRanger "rating" in the US? I stand to be corrected if proven wrong!
However you can be "checked out" in JetRangers there
Donīt know any schools in the area though. Sorry about the hihjack, just thought you should know if you didnīt
Just to inform non-JAA members: In JAA land all helicopters require you to have a (type) rating in your licence for each helicopter type. And a annual proficiency test is required for each and every type with a flight examiner.