There is a Michaels and Hobby Lobby near me, both of them put their drawing pads on sale pretty regularly and you can pick up a big one for cheap, $5-10, I usually get a few when they are on sale to use later.
If you want to buy online, try finding somewhere that will sell in bulk so you make up for your shipping. When you check prices online, make SURE you include shipping in the cost. Its often more expensive than the item.
I found out at least for me that it's cheaper to buy it locally than online. Blicks, utrecht, Flax (only in san francisco I believe), Michaels! I usually get my paints at Michaels but they have all of what you want too. Don't go to michaels unless they offer a 50% off coupon which makes it usually a couple bucks cheaper than the real "retail" price.