I'm sorry about your boy's diagnosis. I don't have personal experience but friends of mine adopted an older blind greyhound (PRA) within the last year. She may see this and respond. Anyway, he has done amazingly well adjusting to the loss of his previous home, being returned to a kennel situation and then being re-homed. He just goes with the flow. They did some reading and research, and were fortunate to be able to contact the owners of some of his littermates who have lost their sight due to PRA and they were an excellent source of information and comfort to them.
I don't know if you've checked into it, but there are message forums dedicated specifically to blind dogs and they could also be a good resource for you. I know Yahoo has one that's been around for about 10 years and has over 3,000 members. I'm sure there are lots of others out there as well. http://pets.groups.yahoo.com/group/blinddogs/