A Gmail address used to be available only by invitation, but in 2007, Google made Gmail available to everyone. Gmail has a huge storage capacity and can also be viewed on your mobile phone. The growing popularity of Gmail makes it likely many people have a Gmail address, which would make it important to be able find someone's Gmail address.
Search Google or another search engine using someone's name. Narrow your search results by adding their town and state. If you don't know their town or state, add a name of a company where they've worked or anything else you know about them to bring up results.
Visit the websites in your search results to see if you can find someone's Gmail address. If you don't find their Gmail address but you do find another email address, try emailing them there and asking them for their Gmail address.
Message someone through a contact link you find on one of the websites in your search results. Ask them for their Gmail address.
Go to Facebook, MySpace or any other social networking site. Search someone's name. You won't be able to see their email address, but you can send them a message through their personal page on the website. If you find more than one person by that name, send them all messages and explain who you are looking for. The right one may respond and you can ask them for their Gmail address.
Enter someone's name on "Email Lookup" on Intelius.com, along with their city and state, if you know that information. The service will display several letters in the email address. Guess their email addresses using the letters provided and send them emails at each one, explaining who you're looking for. You'll receive mailer daemons for any invalid email addresses.