Even with the use of search engines like Google and Yahoo to find websites people still type web and email addresses. Having an inadecuate domain name can become a serious handicap in your business. This situation was evident for a client I recently worked for.
When selecting a domain name test how easy it is to remember it, type it, and spell it. Use the same name of your company or your brand, avoid dashes and underscores, and avoid abbreviations.
.COM is still king, and you should try to get a .com domain. The exception would be county-specific commercial domains such as .co.uk or .com.mx. If getting a .com using your company or brand name is difficult try longer domain names or use of prefixes and suffixes such as mycompany.com, companyinc.com or companyonline.com.
Once you find the .com go and register also the other types such as .net, .us, .biz. You want to make sure that any reference to your domain points to your website. You can configure your server to redirect all your domains to your main .com domain.
If you end up with a domain name that is too long you may have issues with your email addresses. One solution is to have a separate, shorter domain just for your emails. You can use abbreviations of your company name or remove the vowels, for example cmpny.com. In that way email address are easier to spell over the phone and require less typing when filling a form. You can configure your server to receive all emails for a user in the same mailbox regardless of the domain used.
Make it work, people