You might be better off asking over at
http://www.bgafd.co.uk, as the forums there are frequented by a lot of UK Producers/Directors. Also try
http://www.ukadultproducers.com too.
You're probably better off shooting content for the web, as I used to distribute R18's in the UK, and I can tell you that the laws really don't favour DVD producers. There are no such problems shooting for a website. If you like, drop me a PM and we can chat, as I'm planning to shoot some of my own stuff in the near future.