Both Network Interface Guide and Storage Design Guide are included in the SDK, which can be downloaded at http://software.intel.com/en-us/articles/download-the-latest-intel-amt-software-development-kit-sdk
It's my understanding that IAMT.lib source code is not made available, just like IAMTSDK.dll. I personally thing it's a bummer, but they have not documented the protocol for 3PDS, SOL or IDE-R. I jsut checked www.openamt.org, if one day it's posted, it would be on that site. Maybe it would bea good idea to go there and ask for it.
On the other hand, we certainly don't want to discorage people from building software that makes use of 3PDS. If there are any concerns with the licencing, please let us know.
Ylian (Intel AMT Blog)