This has been done many times by others, but just a quick tip on how to add or remove www. from your website’s address. This is helpful for URL canonicalization and user experience consistency. You can also achieve SEO-friendly canonicalization using rel="canonical". Oh boy, I’m getting too technical 
Here’s the juicy part:
Add the following to the .htaccess file in your website’s root folder (often named public_html or www). If there’s not a file named .htaccess, you may create it. If you are creating the .htaccess file, set the permissions to 644. For security reasons, you don’t want others to be able to write to this file.
Note: These snippets are for http:// only, not secure https:// URLs.
Add www.
Options +FollowSymlinks RewriteEngine on RewriteCond %{HTTP_HOST} ^example.com/?(.+)?$ RewriteRule ^(.*)$ "http\:\/\/www\.example\.com/$1" [R=301,L]
Remove www.
Options +FollowSymlinks RewriteEngine on RewriteCond %{HTTP_HOST} ^www\.(.*) [NC] RewriteRule ^(.*)$ http://%1/$1 [R=301,NC,L]
This will work with the majority of web hosts in my experience, but not all.
Additional resources
For more .htaccess information, and great follow-up reading on .htaccess, check out corz.org’s tutorial and second tutorial on some of the most-used .htaccess tricks.
