If you have Word 2002 or 2003, you can use Format | Background | Printed
Watermark, choosing "Picture watermark." In Word 2007, it's Page Layout |
Page Background | Watermark | Custom Watermark...
For earlier versions, see "HOW TO: Create a Watermark in Word 97 and in
Microsoft Word 2000"
http://support.microsoft.com/?kbid=211324
