The world of Digital Asset Management will look significantly different in 12 to 18 months with the introduction of Light Room, MicroSoft's Expression Management (Iview), and others, including curently available Aperture.
I use two tools to effectively manage my photos.
1.
Photo Mechanic is an effective and efficient tool for sorting, applying IPTC stationery, and creating custom configuarations
2.
IView Media Pro 3 is one of the best tools for cataloging files
Following is a link to an article from Luminous Landscape on Image Asset Management that describes a straight forward work process.
http://www.luminous-landscape.com/reviews/software/asset-management.shtml
These tools currently make DAM a much easier and straight forward process to implement. I hope that you find this information helpful.
Marc