Windows Mobile MSDN Home
http://msdn.microsoft.com/en-us/windowsmobile/default.aspx
Everything you need to get started, code, test and deploy your applications can be found on the Windows Mobile MSDN portal.

Windows Mobile Community Team Lead
http://blogs.msdn.com/croman/
Constanze Kratel is a Community Program Manager with the Microsoft Windows Mobile team. She blogs about everything mobile and what’s going on for mobile developers.

Windows Mobile Development Team Twitter is at http://twitter.com/wmdev

Windows Mobile Team Blog at http://blogs.msdn.com/windowsmobile/ is a great place to stay up to date on Windows Mobile.

Windows Mobile MSDN Code Gallery
http://code.msdn.microsoft.com/Project/ProjectDirectory.aspx?TagName=Windows%20Mobile
The Code Gallery is a great place to jumpstart your development knowledge as well as source some help.

Smart Device Development Forums
http://social.msdn.microsoft.com/Forums/en-US/category/smartdevicedevelopment/
The Smart Device Development Forums is a great place to learn, share and ask questions when you need help.

Windows Marketplace for Mobile Forums
http://social.msdn.microsoft.com/Forums/en-US/mktplace/

Windows Mobile Developer Portal at http://developer.windowsmobile.com/