http://www.imsglobal.org/specificationdownload.cfm
You can now download the various IMS specification documents packaged as an IMS Content Packages themselves. The advantages, as their feed says, are that “by downloading the specification as IMS packaged content, you can see what a content package looks like and how it is organized. You can also import it as a learning resource into your Content Packaging enabled learning management system or repository.” – SWL