Since the new resources section is missing most articles about hooks. and the hook overview help article in the IPB admin is also missing, can someone post a very basic overview of how hooks are created and implemented within IPB templates?

I thought they were missing too but they're not. They were NOT written by IPS staff, so they are not in the official documentation section, they are in the Community section.

All the community written articles are at http://community.invisionpower.com/resources/articles.html?category=28

Under the Developer Articles tabs are the hooks articles to which I think you're referring.

Yeah thanks there were some helpful articles there:

http://community.invisionpower.com/resources/articles.html?record=333