There are numerous factors to keep in mind when selecting a domain name. For one you might like to include your keyword in it if possible. Secondly you should do a little research to see if someone else has previously used the domain. This could have both positive and negative impact. If it was a quality site with inbound links you might reap some benefits but if it was a banned spam site you could still be banned from Google for a long time

How we'd know if any domain name expired?