Kijken,
For your ATP I can recommend All ATPs inc. Did the FAA ATP 2 years ago in a few days. They have different programs that will suit you.
www.allatps.com
Other than that, there should be a document on
www.JAA.nl named 'conversion' that describes FAA <-> JAA. Or check FAR 61 on the regulations section of
www.landings.com
cheers