I have always found the people at PetMac to more than a bit scattered. Would not be my first choice. Also the store never seems to be clean.
Try Krisers at Cathedral Commons. They are great and super helpful and nice. They have everything you need to get you started from food, beds, collars, leashes, treats, shampoos, brushes, etc.
I agree with previous PP's that sometimes it is easier to get supplies on line but if this is your first pup I think you need to actually go to the store and talk to people.
Good luck and congratulations!
