Shrimper
Fish Addict
Aquatic Design Centre in London, on Great Portland Street. They're about £2-3 each, as I recall. Appear to be hardy and adaptable, though they quite obviously need a tank with a sand not gravel substrate (mine spend most of the time underground except for the siphon and the top of the shell). No real impact on snail numbers, but it's fun to see them hunting anyway.
Cheers, Neale
Thanks Neale, I keep that in mind if i'm ever down in London and keep my eyes open for local ones.
At least i know there are some in the UK now so fingers crossed i will find some eventually.