I know I've expressed my love for Etsy in the past - and here's another great shop I am so excited about - Pillowhappy! Her work is fabulous and so unique. I have my eye on her "Modern Poppy Bookends."
Retails for $22 for a set of two. Would make a great gift! I love that they don't look like your average serious bookends - they really are so chic: etsy.com. Her blue pairs and purple eggplant bookends are worth taking a look at as well. At first I thought they would look fantastic on a clear acrylic shelf - and I'm sure they still would, but then I saw this:
I fully understand that not everyone will appreciate the color coordination in the same way I do, but this "Viktor/Stodis" wall shelf from Ikea (ikea.com) really does work. It retails for about $6 and is the perfect size; length - 29.5" and depth - 11". While the mere thought of going to Ikea with a 16 month old really frightens me, it's worth it for items like this (I'll have to bring lots of snacks). You'll have to bring your bookends with you to mix and match.
Quick Tip: If you go with both colorful bookends and a colorful bookshelf, keep the book-cover colors as neutral as possible - it's much more pleasant on the eye and will enhance the richness of your shelf and bookends. Go with more colorful books if you choose a more neutral shelf.