This is a hostel with modest facilities. You can sleep for 40 bolivianos if you want heating, or 30 bolivianos without. The winter is particularly cold here, so if you do want to risk staying without heating, bring a sleeping bag. If you have a shower, the rate rises to 50 bolivianos. You can stay in similar places more cheaply elsewhere in Uyuni.
A small hostel, bright, and relatively inexpensive, on Avenida Potosi. You can sleep here for 30 bolivianos, and breakfast is 16 extra. Very good value. Tours can be booked for 600 bolivianos, including three days in nearby parks. Or you can spend 180 for a day trip, not including the parks.
The Hostal Versalles belongs to the Hostelling International chain, and is close to the bus station, which is very handy if you arrive late at night like I did. It's also quite close to the city centre, which is at 2500 metres above sealevel and has a nice, temperate climate. It has a pretty nice garden. It features an internet cafe, telephone booths, laundry, etc. It's very close to "The Court", the largest market in Cochabamba, which I recommend visiting.
This is a good place to sleep. It has a good atmosphere. The only inconvenient thing is that it's an Irish hostel and the speak English there. They do know how to speak a little Spanish there, at reception. There are also in Cusco and Arequipa.