Before you push "add to cart" on that MUST HAVE item, be sure to check out these other lesser-known curriculum sellers for used or gently used/new curriculum.
(This post contains affiliate links. Please see my disclosure policy for full details.)
With a combined purchasing power, this FREE buyer's co-op allows homeschoolers to buy curriculum for a much discounted price. While it is difficult to purchase ALL of your curriculum this way, this is a great resource if you are looking to buy a high-dollar curriculum all at once, such as Rosetta Stone's foreign language courses. I was recently able to snag a magazine subscription to God's World News for my kids for less than half the price.
This curriculum "yard sale" takes the bidding wars OUT of buying gently used curriculum. Not only can you find curriculum to fit every teaching method and learning style at great prices, you can also find manipulatives, games, and all kinds of homeschool extras. (Be sure to peruse the "groups and activities" section for homeschool happenings in your area.)
Although this family-run, on-line bookstore may not offer the volume of new and gently used materials that other sites do, the catalog system is SUPER easy to navigate and very organized. After two or three CLICKS, you instantly know if your book is available and its price and condition.
While this site is less user-friendly than others, it is a nice option when looking for some of the more well-known homeschool curriculums like ABeka Book, BJU Press, Apologia, and Math-U-See. As this is a third party site that sells used curriculum for others, the prices are a bit higher than Homeschool Classifieds.
Run by a fellow homeschool blogger buddy, Free Homeschool Deals is the homeschooling-deal-finding-momma's best friend. While you will not find curriculum for sale, you WILL find FREE resources from around the web and the latest info on shopping discounts and curriculum coupons.
And here's a BONUS site...
Dedicated to providing inexpensive NEW curriculum for the homeschool family, Rainbow Resources is a great ALL-IN-ONE curriculum site. Often times, I am able to find my "boxed curriculum" sets cheaper here than from the actual publisher. That being said, this site does have higher shipping prices than other sites. Bulk orders receive discounted or free shipping. Consider ordering with a friend to receive the best value.
Know of a great site for buying inexpensive curriculum NOT listed above, be sure to leave a link in the "comments" so we can all go shopping!