If you would like to use GooleApps with your domain, you may setup your account from here. Once you have signed up for  GoogleApps account, you would need to change the MX records for your domains. This could be easily done through your cPanel -> MX Entry. Select the domain for which you will be changing the MX records and remove any previous MX entries for that domain.

Then add the following MX records with the corresponding priority for your domain:

Priority: 1 ASPMX.L.GOOGLE.COM
Priority: 5 ALT1.ASPMX.L.GOOGLE.COM
Priority: 5 ALT2.ASPMX.L.GOOGLE.COM
Priority: 10 ASPMX2.GOOGLEMAIL.COM
Priority: 10 ASPMX3.GOOGLEMAIL.COM

The above instructions are in full compliance with the official Google Apps instructions and have been adapted to work with cPanel. It may take up to 24 hours for these changes to propagate and take effect.Then your mail services will be handled by Google Apps Mail.