I do a lot of work with small offices on the side, and consequently I have to write a lot of VBA code. I tried writing some of that in C# and ended up wrapping the Office Automation interfaces automatically with Visual Studio.NET. Fortunately, Microsoft has released the blessed Microsoft Office Primary Interop Assemblies. There's also a tutorial which touches on the importances of PIAs in bridging the .NET to COM gap.
Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. I am a failed stand-up comic, a cornrower, and a book author.
Disclaimer: The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.