You might try calling Buckminster gliding club at Saltby airfield (just off the A1 near Grantham, website findable via
www.buckminstergc.co.uk).
I flew my glider there last summer, and was told that they were doing a lot of motor glider training. Added to that, they were very friendly, laid back, not crowded (during the week) and helpful. It seemed to me the kind of club which might put together a course for you - worth asking.
And for glider pilots, worth a visit.
Closer to home, have you asked around at Shobdon? I've not flown there, but they aerotow and there's a busy aero club as well (
www.shobdon.com).