I want to set up domain mapping so users choose their domain name

I followed all of the setup instructions for the domain mapping plugin, I added the sunrise.php file to /wp-content. I edited the wp-config file with define( 'SUNRISE', 'on' );

When I go to the domain mapping plugin settings, there is no mapping options/reseller options tab, just a screen that says "domain mapping configuration." I do not yet have a reseller plan with my host provider, do I need to do that before those tabs will appear?

I can manually add domains to the network ie mysite.com/usersite, but would like to give people the option to choose their own domains when setting up a site and currently cannot do that. Thanks for the help.