Prague I Guide - a fully comprehensive and independent insiders guide to the city. If you are using a car, make sure you park it legally as it will be swiftly clamped otherwise and, of course, leave no valuables in it.
Car theft is lower than in Western Europe but steadily increasing.
There are quite a few car rental companies in Prague including most of the major international firms. A Czech car rental will normally be significantly cheaper than the international ones although your choice of car may be limited to your favourite model of Skoda.