Not all keywords are created equal. People search for some keywords thousands of times a day. Other keywords are not so popular. You can find the keywords using the free Google Keyword Tool. Or, if you have money to spend, you can try Keyword Tool or Long Tail Platinum.
Once you know which keywords work best for you, it’s time to find a domain name. A number of websites can help you find a good keyword-rich domain name. A couple of free ones that look useful are Name Mesh and Lean Domain Search.