As he is in Germany he is very much out of reach for a small claims court even if they recognize that in Germany ? You would have to serve it there.
I would get back in touch with him and get as much personal info from him as possible. It may take a week or two to build up his trust. But when you have his address / phone # you can then sign the fucker up for every offer and deal you can find on the web. Sign him up for e-mail news letters, samples of birth control tablets, Tampax samples, etc.etc.etc.
It's a lot of work but if you feel strongly enough you can fill his mail box up with shit every day and have him harassed by telemarketers day and night
