This was a pain. Basically mount the .iso
Download imagex.exe from here http://www.tipandtrick.net/2008/imagex-600118000-x86-and-x64-for-windows-server-2008-and-vista-sp1-standalone-download/
This explains what to do with it http://4sysops.com/archives/how-to-mount-a-wim-image-with-imagex-in-windows-vista/
Right click on wimfltr.inf and then click on “install”
Reboot.
Create a new folder this will be your mount point mine was c:\test
Run the command imagex.exe /mount d:\sources\install.wim 5 c:\test
Now you can search for usbd.sys in the c:\test folder
Or you could just download it from here (this is the 64bit version for server2008 enterprise)
http://sites.google.com/site/mellerbeck/Home/usbd.zi?attredirects=0&d=1
rename to a .zip and unzip
Michael Ellerbeck 
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