Another option, more expensive than IKEA's "Billy", is Wood You Furniture in Ocala. They have unfinished but real wood bookcases by Inwood. The bookcases can be finished to complement your style of furnishings. They usually have coupons in the "Newcomers Guide".
The following Inwood site shows the style of bookcases they offer:
http://www.inwoodfurniture.net/bookcases1.html
I bought two tall bookcases to make a "library wall" in my home. Chose to paint them the same color as the woodwork, rather than stain. I took it slow and did all the requisite sanding, priming, sanding again, etc. I'm very pleased with the results. I got the style I wanted, in the finish I wanted, and at considerably less than the furniture stores could offer. It was a satisfying project.
Wood You is at 1510 SW 17th St; 352-732-6611. I hve no affiliation with them other than being a satisfied customer.