I'm not in your area, I run a firm, our local building merchants often give out our details to customers who ask for recommendations as they know we are reliable, go and find the nearest travis perkins, and ask who are the best. it's worth a try,
check the contractors insurance, and then ring the insurance and check that the insurance is still currant, lots get the certificate then stop payment, we are insured up to ten million, so anything goes wrong, you can claim against it, even years later, that way you have it covered,
beware of the web sites that recommend builders and have"customers" reviews, all the evil con cowboy ones around here are heartily recommend on them, they obviously spend more time faking reviews than they do learning about building.
and be suspicious of anyone who instantly available, we are booked up for the next three years, there is a reason for that, I would probable find a way to fit you in, but it wouldn't be in the next month or two, unless i had a hold up else where.