I've met plenty of wonderful deaf dogs when transporting. I generally make sure they see me as I approach, unless I know they're the kind of dog who won't snap at you if you startle them (none of them have, actually). If they're not looking your way, stamp your foot on the ground. The vibration will often get their attention. Flicking a light might also get their attention if you're in a room.
As someone else mentioned, hand signals are key. Dogs are masters of body language and so learn from hand signals very well. My dog (who does hear) knows her commands through both hand signals and voice. I figure if she ever goes deaf when she's older, she'll still be able to respond to commands that way. I can do completely silent training sessions with her and do, in fact, do them sometimes (on the flip side, I do all voice commands at other times).
So definitely don't be put off by deafness in a dog. Sometimes it's almost impossible to tell the dog IS deaf they're so responsive to other stimul.
Regarding whether or not the dog was deaf. What kind of dog is this? Is it predominantly white? Pink around the eyes? Blue eyes? Butterfly nose? Not all dogs who are born deaf are white factor, but you do see a lot of white dogs with vision/hearing impairment in some breeds: Australian shepherds, Great Danes, Pit Bulls, Dalmatians, and Boxers are known for it, I believe. The deaf dogs I've met (mostly Aussies, one Catahoula) have had a particular "look".
Here are a few pictures. All three of these dogs are deaf, but not vision impaired despite the odd looking eyes.
Jack
Tanner
Tucker