L.A.
Hi K.,
I do love Target; however, I recommend that, for the first fitting, you go to Stride Rite or Nordstrom and have him fitted by someone who knows what they are doing. Shoes are such an important part of a child's development and are often overlooked; however they affect posture and ability, so....it's worth the extra bucks. Once you get a good feel for his size, you can start shopping Target, etc.
Hope that helps and congrats!
L.