Adding images to filetypes in SharePoint

First, you need to obtain the images of the icons you want and make sure they are 16 x 16. Then, upload them to the sharepoint server, in this directory, C:\Program Files\Common Files\Microsoft Shared\web server extensions\12\TEMPLATE\IMAGES

next, add them to the docicon.xml file located here, C:\Program Files\Common Files\Microsoft Shared\web server extensions\12\TEMPLATE\XML .

do a iisreset and you are done.

these need to be scaled down.