The Barnes & Noble book store in Walnut Creek is huge, has a great selection and has a friendly staff to help in finding particular items. There are also several places to sit down and read while you are there. They are open from 9-11 everyday which is convenient. The only downside is that the bookstore is located in Broadway Plaza where parking tends to be a bit scarce. But, if you don't mind walking a couple of blocks, there is a public parking lot near by.