I am all for using a harness on a very young puppy. They do not promote pulling if you don't ever let them pull in it.
I know this is a bit of a late response, but go here http://www.dogstardaily.com/free-downloads and download the free book After You Get Your Puppy. There are tons of great tips in there on everything from leash walking to teaching bite inhibition to socializing.
Also here is a link to a great trainer on youtube who has a lot of training tutorials, including leash walking. http://www.youtube.com/user/kikopup
Good luck!