NLS, do you hold the JAA ATPL or just the "frozen" ATPL?
With a ICAO CPL or ATPL:
14 CFR 61.151-61.167
61.153 (3) is the one you are interested in.
It reads (amongst other things) :
(3) Holds either a foreign airline transport pilot license with instrument privileges, or a foreign commercial pilot license with an instrument rating, that
Which means you only need to take one written test and a flight test in an aircraft of your choice.
If you hold CPL-IR "frozen" ATPL then you don't meet the 1500 hr requirement for the FAA ATP. The most you can get is a FAA CPL-IR.
The following steps are required:
Apply for the FAA PPL based on your JAA CPL
- Instrument written test
- Instrument practical test (you will need about 15 hrs of training)
- Commercial Written test
- Commercial Practical test (about 20 hrs of training, 10 for ME and 10 for SE)
Applying for the FAA "piggyback" license:
Airmen Certification: Verify the Authenticity of a Foreign License, Rating, or Medical Certification
US regulations are here:
Electronic Code of Federal Regulations:
Cost:
Written test $150
Flight test $350-$550 depending on region and examiner
Flight instructor $40-$80/hr
Airplane cost depends on where you choose to train
Visa/TSA approval/fingerprinting $500
You can train anywhere you like but it needs to be a Part 141 certified school in order to be able to train Foreign Nationals.
Federal Aviation Administration - Pilot Schools