Here are some links to information about Altiris 7.
This says migration but is equally valid for a first-time customer:
https://www-secure.symantec.com/connect/articles/altiris-endpoint-management-migrations-and-upgrades-71
Product documentation is located here for various suites:
http://www.altiris.com/Support/Documentation.aspx
KnowledgeBase is located here for all Symantec products, including Altiris:
http://www.symantec.com/business/support/index?page=home
This implementation and planning guide explains quite a bit about design and architecture and is good for a high-level orientation on the product, including guidance on multi-site installations:
http://www.symantec.com/business/support/index?page=content&id=HOWTO9811
You should know that a major release will occur on March 7 when version 7.1 is released. It looks a little different compared to the 7.0 release you downloaded, but offers many feature and performance increases.
I don't know of any evaluation walk-through guides, but you may want to view the articles and videos on this site by going to Articles or Videos instead of Forums. You can sort that content by product (e.g. Client Management Suite) or topic (e.g. Installing). This would lead you, for example, to this video on installing CMS 7 by Blair Thomas:
https://www-secure.symantec.com/connect/videos/client-management-suite-7-cms-7-installation-demostration
Does this help get you started on your eval?