In terms of finding actual users, the machsupport forums, and cnczone will be your best bet.

Personally, I like geckodrives, but they can get a bit expensive trying to get them on this side of the pond.
There is now an official UK distributor, but it's almost as cheap buying direct from Geckodrive, or from any of the other foreign distributors. Especially if you need to buy stuff from one of the other suppliers anyway.