Determine MIME type

I need a way to determine the MIME type of a file from a Windows Forms application.

I have an import application (Forms app) that accepts digital media. So a person could give me a JPEG, Word document, MPEG 4, or whatever.

This importer needs to determine the MIME type so I can save a record in a database table with the proper MIME type.

A web application uses the database record to serve the mime type properly, so therefore, having the proper MIME type is rather important.

I thought of hard coding against the file extension, but that's rather kludgy.

text/richtext
text/html
audio/x-aiff
audio/basic
audio/wav
image/gif
image/jpeg
image/pjpeg
image/tiff
image/x-png
image/x-xbitmap
image/bmp
image/x-jg
image/x-emf
image/x-wmf
video/avi
video/mpeg
application/postscript
application/base64
application/macbinhex40
application/pdf
application/x-compressed
application/x-zip-compressed
application/x-gzip-compressed
application/java
application/x-msdownload

Any suggestions?