If you are planning to visit Prague for just a few days I would suggest that you just pick up a free guidebook once you arrive in Prague (or download this one). Most guidebooks about Prague have hundreds of pages and you won't be able do everything that is recommended during a short stay. However, there are a few pocket guidebooks, which are just right for a short weekend break. Probably the best one is from Lonely Planet - Best of Prague, as it is the most up-to-date one. In other guidebooks we found that some information was out-of-date, but it should not affect you that much. Other recommended guidebooks for short visits are: Berlitz Prague Pocket Guide, DK Prague Pocket Map and Guide, Prague City Spots from Thomas Cook, and the AAA Prague Guide. If you are staying longer (more than a week) we recommend Rough Guide to Prague, Lonely Planet's Prague and Time Out's guide, Prague.