kwstas
I think the sort of thing you are talking about is what is called a Part 141 course the United States. This is the closest equivalent of the integrated courses that exist in Europe but, as has been said previously, there is no frozen ATPL in the US. You complete the ATP after you have 1500 hours and the course includes a written test and a flight test. This is usually done under Part 61 which basically means the course is unregulated by the FAA. Bear in mind that Part 141 courses are still modular in that you do them separately (the Commercial must be done at the same time or after the Instrument) but they are inspected by the FAA and there are some concessions on minimum hours. Also, there a few schools that have examining authority which means that they can declare you competent without the need for a test from a designated examiner.
Do you intend to fly in Europe or do you have the right to work in the US? If it is the former you will need to think about conversion and also, whilst you are doing this, the need to keep your licence valid and have medical exams done to FAA rules (every 6 months for ATP). Note also that there is NO way of converting an FAA ATP to a JAA ATPL without airline experience, you have to sit the ATPL exams and convert it to a CPL/IR (in effect, a frozen ATPL).
If you need to ask anything else, please PM me.
pilotincommand