Admit it. You love books. Not just in that, "Yeah, I could look at a new book," kind of way, either. You love books in the way that makes you ponder just how many books you can put on your kids birthday lists and still make it look like they were the ones who made the selections.
Not that I've ever done that or anything. :-)
Enter Homeschool Library Builder.
In addition to your routine search by subjects, Homeschool Library Builder also has a tool that allows you to narrow your results by curriculum. I entered "Ambleside" as a search term and was rewarded with books in the Library Catalog listed by Ambleside Online Level. I noticed that this was a possibility with Tapestry of Grace, as well, and know that something like that would take a lot of work out of the more labor-intensive curricula available.
Memberships are available, but they are free. Essentially, you are just creating an account to make purchases, with one important caveat: for each dollar you spend, you earn a Book Point. Fifteen book points translates to $1 in your account to use toward future purchases.
The company also offers a newsletter, fundraising options, referral bonuses, and more. Definitely something to add to your bookmarks!