You're welcome to use Google Apps to set up mailboxes at your domain. The best way to do this is to point your Name Server records back to your registrar, then modify the DNS to point to liveBooks for website hosting. This can all be done within your domain registrar's control panel:
- Unless your current email account has been set up as a POP (which downloads everything to your computer's hard drive), you'll want to back up your email before making any DNS adjustments. We have compiled information on the backup process here: How do I back up my emails?
- Point the Name Servers for your domain back to your domain registrar.
- Modify your domain zone records to point to liveBooks for hosting the website, using the server settings listed in the Forum here: What are the liveBooks CNAME and A Records?
- Google Apps will require you to verify ownership of your domain. Through your domain registrar, you can create a CNAME or TXT record in your domain's DNS settings. You can find more information here: Google Apps Administrator Help: Verify domain ownership
And detailed instructions on setting up MX records at various host/registrars here.
Once you've verified your ownership, Google Apps will activate for your domain, and you can set up mailboxes through this service.
The screenshot below illustrates how records should be set up in a GoDaddy account: