Tieguyuk is a very good website with lots of pictures and a few videos of TUG's. On here, you can fill in a form and then get tied up by the runner of the website! You can either come to their house in Essex or let them come to you.
Although you have to have an account to see all the pics and vids, there are still quite a few free ones that you can see without having an account.
It's a pretty good website!
Here's the link:
http://www.tieguyuk.com