I used the gentleman whose website is DriveIndia.nl - Drive India - the site is in Dutch, because a customer set it up for Sushil, the owner / one of the drivers, but he speaks perfect English.

He was our driver for a 2 week trip around the Golden Triangle, his van was clean, comfortable, with good AC, he was polite, intelligent, and told us lots about the region (but could read the mood and was quiet when we wanted him to be because we were tired etc.) He was a good driver too - which matters! He knows guides at lots of the popular sites (guides have to be licensed to work at specific sites I believe) so was able to take care of all the little details like that and made some excellent recommendations for meals. He also saved me being preyed upon by a snake charmer - I had mentioned I hate snakes, and he saw a guy approaching me with a snake in a bag in Jaipur, and he literally ran between me and snake guy telling me to get back in the van and screaming at the man to take his snake away (although ruder, one suspects) Apparently they put the snake on unsuspecting tourists until they are paid to take it off them - eeeuuugggghhh!