My big brother used to be heavily into trials riding, used to 'passenger' on a sidecar outfit, did the manx tt trial, and european events and allsorts. But he isn't into it anymore and he isn't in the West Brom area anyway so he couldn't help (I asked)
I do remember there being lots of adverts for clubs and events in the 'Trials and Motocross News', that might be a good place for them to start looking.
The other place that might be able to help is 'Wheels' over by the NEC.