Rates for IT...

Recently I've been doing more and more computer work. Most of the time it's just building computers. However, there's times where I can spend a whole day or two working on peoples machines. (Computers, Game Consoles, etc.) I have not yet been able to place my finger on a standard pricing plan. So I decided to shop. I looked around a few local computer shops and some of the prices ranged from $200.00-$500.00 for a computer build. (No parts -- just labor) This seems way outrageous and I doubt any of my "customers" would continue to use me if I charged those rates. My major question is what would other's recomend for the following:

• 
  General Computer Checkup and Maintainance
  Computer Build (Just Labor)
  Computer System Consulting
  Tailored In-Home Computer Installation(s) (set-up, etc.)
  Tailored In-Company/Business Computer Installation(s)
  Virus and Spyware Removal (Manual)
  Company-Wide Virus and Spyware Removal (Manual)

Any help suggestions would be appreciated.
For background; I'm a bit slow due to physical limitations but I'm VERY thurough and very good at what I do. So let me know your opinions, thanks.

If you are thorough - you should charge for that. I really don't know what a computer goes for building it from scratch, but we are in the process of buying one from Dell - costing about $5,500.00.

If you can, you might consider adding an hour of time in walking people through some of the programs. Or maybe setting up different profiles. Charge to make yourself a decent living, but give your customers something that other people are not