QUOTE(mari86 @ Jan 24 2013, 08:09 AM)
Domain hosts run DNS servers for your domain. These are used to configure A records, CNAME records, MX records and TXT records. Most domain hosts offer domain name registration, as well.
Since Google Apps is not a domain host, you'll need to modify your DNS records with your domain host to set up the Google Mail service for your domain. See Identify your domain host if you don't know which company is hosting your domain.
You also need to modify your DNS records if you are going to use custom domain on your free blogger sites