Something went wrong!!

installed wp fine, uploaded theme fine then I went to setting and change the blog and wp url to http://www.iprintusa.com from http://iprintusa.com and now I can’t access wp! How can I change or fix this?

The reason I made this change was because the site was not accessible when you typed in http://www.iprintusa.com only when you typing in http://iprintusa.com. After I get this issue fixed, how can I make the site accessible both ways?

Do I need to move the files from the http docs or something like that so the installation I did points to the correct url?

Thanks!