Dear Snood, if it's JAR ATPL theory you're looking for the answer's nowhere mate! You need a training provider who is approved for ATPL modular training by one of the JAA member States (most commonly UK CAA), but even these are now thin on the ground. Best bet could be to try distance learning method with a European (probably UK) training school who offers these, but bear in mind the course includes 2/3 weeks residential part! You'll need confirmation of attendance before entering the exam process
Try this link
http://www.caa.co.uk/docs/33/SRG_FCL_APPROVEDFTOS.PDF
Good luck!