Suggested resources for finding private instruction?

Google doesn't seem to be the best place to start, as the topic is ambiguous enough to get muddy results.

I'm looking for a reputable UB instructor in Massachusetts (specifically Arlington,) and am unsure where to start digging. Are there any good resources or is it a word-of-mouth sort of process? I've been digging in the forum for the last few days but don't have any good leads.

Suggestions are welcome.

Thanks!