Radeka's (Pronouned 'Rad-ick-a') is probably the best of the bunch in way outback Coober Pedy.
It is centrally located and a five to ten minute walk from the Greyhound terminal. However, they will come and collect you if you book in advance. This was a welcome surprise considering we arrived at 5.40 a.m.! They will also return you to the terminal when you leave.
The hostel itself is part of a greater motel, with motel rooms on the surface and the dorms underground. Reception is very clean and has a bar, pool table, free tea and coffee, internet and an opel shop. Beware that internet is rather expensive, although it does have a card reader for digital cameras and CD burners.
Before you reach the dorms' security door, you'll find a TV room with dilapidated sofas and a large well-equipped kitchen, both of which are very clean. The dorms are accessible via a secure code-entry door that lead you immediately to the bathrooms. These are unisex and, although clean, there are no locks on the shower doors.
Downstairs, one arrives at the underground lair of the dormitories. This is a loose term, as the dorms are more like caves with wide openings. Security is therefore nonexistent as there are no doors on the dorms. The doubles and twins do have doors if this is a concern. Dorms themselves are either separated by a thin wooden wall or solid brick wall, but be aware that all sounds can be heard anywhere in the underground complex. It's spotlessly clean down here, with a minimal lighting system. There are no powerpoints in the dorms. Radeka's only provides a bottom sheet and pillowcase -- no top cover. They will however let you borrow one with a deposit, but they'll keep a part of the deposit so there is a small charge.
Radeka's also does a tour of Coober Pedy, but only if there are four of you or more. When we booked, there were less than four of us, so they booked us onto an alternative trip with another agent (Stuart Caravans) that actually turned out to be cheaper and a good half-day trip from 1 p.m. to 6 p.m.
Overall, it's quite a good hostel, let down by a few things like the expensive internet and security issues, but you may disregard these things as you'll probably only be staying in Coober for one day anyway.