Please don't use human shampoo on dogs. It can lead to serious skin problems. Skin problems are much easier to prevent than to cure. Just because your dog is showing no symptoms yet, doesn't mean it's safe. Remember you are not just cleaning their hair you are caring for their skin. Skin problems with dogs are all to frequent. There are many great dog shampoos and conditioners; it doesn't need to be an expensive one. This link give some good information about the proper ph.
http://members.cox.net/jrogan/shampoo.html