Cost Of Living
Qatar is a cheap country to live in if you go to the right place (this depends on your lifestyle and where you're coming from). The government doesn't charge a lot of most things such as water, electricity and home phone lines. Qatar has hardly any taxes. The only one that comes to mind is import tax, but even that is quite cheap. Qatar nationals get free water, electricity and phone lines which is great! Having mentioned that, the only major expense would be with accommodation as of 2008. Location does vary pricing, however living in the heart of the city could be quite expensive.
I've tried to make a general chart of pricing for people to get an idea of things. Remember though, if you are thinking about coming to the country to work and live, while some things may be cheaper other things may be more expensive.
If you are coming with a family and have children, the two main things to think about are education and accommodation since they can be expensive (although there are now government initiatives to control rises). If you've been offered a position, most jobs will give you housing and/or school fees. My personal advice is NOT to be shy to negotiate your salary!