I know that there is no official API for Google Analytics but is there a way to access Google Analytics Reports with C#?
I wrote a small project that lets you generate pretty much any Analytics report. It's listed on Google's Analytics API page - http://code.google.com/apis/analytics/docs/gdata/gdataArticlesCode.html
You can read about it here and get the source code - http://www.reimers.dk/blogs/jacob_reimers_weblog/archive/2009/05/09/added-google-analytics-reader-for-net.aspx