I cook a lot so I end up using a lot of spices. There are a few ways I've found to save money on them. Now, I know that purists will say don't keep any dried spice for longer than a year, but honestly, I haven't had a lot of trouble with keeping them for several years. I'm sure they're better when a year or less in age, but they will work fine for much longer than that.
Places I purchase spices and baking supplies:
BJ's and Costco (and similar stores): They sell larger size containers. These are very nice, but you need to have shelf space or spice rack with tall shelves to hold them. I have about 15 of them, I think. BJ's has been running a coupon in their mailing 1-2 times a year that has been a great savings! BJ's also accepts manufacturer coupons, so you can use the McCormick coupons from the paper since that's what they now carry. Costco is the better of the two for Vanilla. It was $3 cheaper for the same size bottle at Costco the last time I purchased it. BJ's and Costco are also the least expensive places I've found to get honey and maple syrup.
Amish Stores: Up in Pennsylvania, there is an Amish Store called East Drumore Foods on Little Britain Road N, near Quarryville, PA. Throughout PA, there are small Mennonite and Amish markets similar to this one. This is a great place to get Molasses. I also buy many spices there because they are less expensive than supermarkets, but you can get all the spices that Costco and BJs don't carry.
Mexican Markets/Ethnic Sections in regular grocery stores: Wegmans carries a lot of ethnic spices in their middle eastern food section as well as their Hispanic food section. There is going to be a Wegmans near us soon and I will be glad when it opens. Until then, Mexican Markets carry a good selection of spices in bags that you can use to reuse the bottles you have for your spices (so don't throw those bottles away!).
Atlantic Spice and San Francisco Herb: If you don't live near a store where you can get spices in bulk or larger packaging, there's another option. If you're on the East Coast of the US, there's www.Atlanticspice.com and if you're on the West Coast of the US, there's www.sfherb.com A minimum shipping order is $30, so find a friend or two that you can share some spices with. One thing to note: compare the weight of the packages to the bottle that you have of that spice. I just ordered 8 oz of oregano and I am going to have to find 3 friends to share this with! But, it can be a great way to save money on spices.