Great idea!
You can find Tantric training on Meetup for example; I also had a training session with Ecstatic Joy Temple (London), which was nice.
If you did some googling, you might have come across a place in West London that offers training.
I did first part of their course some time ago and do not recommend it. The man who runs this place has been jailed TWICE (first for running a brothel, years later for assaulting women while doing massages). I personally had the most horrible and revolting experience with this man, so had my friend.
TantraLink would be a good place to look for teachers, I think. I saw only one person from there, for a workshop.
I heard good things about Osho Leela but never visited.
I can send details of my massage school via PM.