Welcome!! How excited you must be!! Please post more about your baby and of course pictures...we must have pictures.
I find that most of the items that PetSmart and PetCo carry are of good quality. Personally, however, I stay away from pet stores that actually sell puppies. Because of where they get the puppies, ie: Puppy Mills, I do not want to support their stores in any way. I realize that these types of stores may be all that some areas have available to them, but for myself, my conviction is to not support stores that keep this horrible industry going.
There are many great members on this board that sell nearly anything that you could want.
The most important thing is a good quality pet food. There are many threads here that give great info, or post and ask specific questions, many are more then willing to help. The only problem is this board moves so fast sometimes that your post will quickly get pushed off the front page.
But keep asking and don't get discouraged.