The Book Escape (located in Federal Hill) has a good selection of new, used and rare books to browse through.
Their website (http://www.thebookescape.com/) is a pretty good resource too: it links you to various things about their store (location, book lists, etc.) as well as gives you some good information on books.
They also rent out space for special events (such as book club meetings) to give you a location to meet up.
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