Office Depot is the place to be this week. They are offering a FREE backpack and lunch sack with any $15 purchase (that's pretty much one thing of ink).
We needed ink anyway so we picked ours up today and they still have lots of everything in stock (except protractors) The backpack isn't a real nice one and certainly isn't big enough for an older child to take to school but it is the perfect size for my almost 4 year old and I LOVE that the lunch sack attaches to the front of the backpack. This will probably be his "toy bag" for traveling and having his own little insulated bag for his snacks will be really handy too. It would be a really handy size for taking snacks and drinks to an amusement park or zoo too PLUS, you wouldn't have to worry if it got lost or stolen.
Also, be sure and check out the $1, $2, and $3 deals in the school supplies for some great deals too. Don't get sucked into buying other school supplies there . . . you will do much better pricewise at Walmart but the deals on the front couple pages are all pretty good and the free backpack well worth it if you need ink anyway.