How can I create an Enterprise ID for our company.

Recently our company has started to purchase ebooks in *.acsm format.

In error took the easy route and created a standard Adobe ID, however we have found that it is not adapt to a mid / large company environment and we really need to be in a position to purchase and share the various ebooks.

I have performed many searches but the only information that I have found is this blog  How do I create an Enterprise ID

However it does not provide an y real information on what is required or the costs. For example do we really need to sign a Creative Cloud for Enterprise ETLA? What options are there?

Any assistance would be much appreciated