A domain name provides an identity to the business. While buying a domain name you need to note down the name of the website domain names and its nearest ones so that if you do not get that particular domain name, then you can go for the nearest one (for example, if you require a mattress website then you can buy a mattresse.com, choosing-a-mattress.com, allmattress.com, bestmattress.com etc)

If you want a domain name for your personal use, then use your name, surname etc. For your business domain name you can go for a domain name with catch phrases. You can check whether the domain name is available or not by searching through www.whois.org.

Its not necessary that you have to get a domain name with .com, you can buy .net.us etc. If you like a domain name and would like to buy that particular name but it is registered with somebody else, then you can contact that person in the administrative contact section through whois search from the website. Sometimes domain name owners sell their domain names. Domain names have value and if the domain name is a unique one, then it could be sold for a higher rate.