Yeah, it's called Motorway car auctions on gate 4 Southampton docks
I live about half an hour away and have been there loads of times. It used to be a dealer only auction but anyone can go and bid now.
There are pro's and cons but IMO buying from there is a bit of a mine field. You can sometimes get a decent car if you know what you are looking for but a lot of the time it is full of the **** that didn't/wouldn't sell at auction in Japan. I suppose 1 good thing is that if you get there early you can at least get to have a good look around the car with your own eyes and that could better than buying from a Jap auction house online.
You can certainly pick up a cheap motor but a lot of them are dogs and with what I now now I wouldn't recommend buying a car from there unless you go into with your eyes WIDE open. Saying that, some people are bound to disagree with me and they may be right. I know that a lot of people also slate Motorway. Best bet is go and have a look for yourself without bidding, see what you think.
I know of dealers who it give all the billy big bollocks about having a buying connection in Japan or say that they go on a buying trip over there every 6 months but I always see them them down the auctions buying grade 3 motors.
In my opinion it's risky