I believe they were from Target. Ikea might be a good place to look as well.

Thanks.

Approximately how many books will this bookshelf hold? What are the colors that it comes in? How much should I expect to spend on this item?

As beautiful as this is all I can think of is that any books you left in there over time will bend, warp and break the bindings. You can see some of the book already curving to fit the slot.