[Joemoplata]

If all you are looking to do is compliment your Judo as you stated in your post, then a good BJJ program is best for you. I say this because in most Judo programs the concentration is on nage-waza, or throwing techniques. This makes sense since the easiest way to score a victory in a Judo competition is with an Ippon throw. But in Judo you can also win with submissions on the ground which is BJJ's strength. So they compliment each other PERFECTLY....Judo for getting the fight to the ground the quickest way, BJJ for submitting someone on the ground the quickest way.

Japanese Jiu-Jitsu is a much broader focus and will cover things that are good for self defense but impractical for any application in Judo.