In my book A Girls Guide to Decorating (which is on its second reprint and has been translated into four different languages - hugest thank you to everyone who has brought) I've written about fattening up standard brought shelves with mdf to make them super gallery esq. Another solution and its way more rustic but also quite lovely is to source reclaimed wood and simply use that as your shelves. The two images below show just how fabulous they can look. I'm a big fan of reclaimation yards and get as much fun pottering around them as I do going to Top Shop! I've made benches and little tables all out of old pieces of fabulous wood. How cool are these shelves?