Ross at Simplehelp has written an excellent tutorial 
with screenshots on how to get your contact information out of the Gmail and into Address Book for use in Mail.app.
The app used in the process is called Address Book Importer , a clever utility that allows the user complete control over how to map the fields for import. It is also free for a single use (although the developer asks for a small donation if you use it regularly).
He has just released a beta version (2.0.5b3) which is a universal binary and features several fine-tuning tweaks.
The interface is clean and easy to understand:
The tutorial even tells you what to do with the mysterious “name” entry that appears when the import is finished.
MailUnreadStatusBar, a discreet Menubar notification utility for Mail.app, has been released as a universal binary, which will run just as smoothly on Intel Macs as well as PPC ones.
Its drop-down menu offers options to open, show or quit Mail and to perform an instant check for new mail.
CTM Development has released a new beta of its email client PowerMail.
A lot of people have been waiting for this.
A new version of Thunderbird is out and it’s a universal binary!
Tapdex is a preference pane that enables you to access your Address Book contacts with a user-defined hot key.
Postfix Enabler is a graphic front-end to built-in services in Mac OS X that helps you to set up your computer to be its own mail server, that is to run its own SMTP, POP3 and IMAP services, with or without SSL support. 
