$50 /hour is not bad. Those saying $110 /hour are insane. people don't charge and make that (well besides geeksquade) anymore.
formatting and reinstall i charge a flat $100. it takes 1-3 hours but most of that is waiting for it to install.
And yet Geeksquad rakes in the customers by the truckload. Every time I'm in a Best Buy the GS desk is multiple customers deep. Almost everyone has computers, often several, and people are willing to pay for what they at least perceive to be quality service. Having fixed a number of units that had first gone through GS service, I can say that a lot of their workers are less than outstanding, although I think some of that has to do with the severely limited scope of tools and procedures available to them due to corporate SAP policies.
'Shadetree' PC repair has gotten cheaper due to a lot of people thinking they know what they're doing and bidding the pricing down. Unfortunately for the industry at large, this degrades the confidence people have in that kind of solution with these independents commonly installing pirated software, neglecting to maintain user settings properly (like getting the NK2 file back in Outlook after a reload, as many users neglect to add contacts to their address book and just use the auto-complete), and often doing unnecessary reloads when more knowledge would let them properly fix the existing loadset. Just think of all of the so-called 'PC Repair' people you've met, most of them are severely lacking in many crucial areas. Anyhow, a lot of these types will offer services at cut-rate pricing as they are unable to develop good service contracts with decent clients, and after someone has a bad experience with a marginal independent repair person, they are less likely to trust that type of service in the future.