Vanilla Alternative nr St Neots have some events, some seem to be with pro girls, most with amateurs. It was great when the Greedy Girls Parties were held there, but otherwise quality is variable and not many reviews on here.
External Link/Members OnlyAlso Jaydees nearby which seems to be strictly amateurs, so YMMV as a single male.
External Link/Members OnlyIn my brief experience of such places, unless you're buff or black, the middle aged MILFs who inhabit such places won't give you a second look!