Advice/Experience regarding online distribution of documents

I'm new to Experts Exchange, but I believe many of you will find this very interesting.

The company I work for has acquired a "library" of industry-specific books, periodicals, photos, manuals, white papers, case-studies, articles, legal documents etc. This library literally weighs in at 4.75 tons. The books, periodicals, manuals and other bound media are being donated to a university with which we are affiliated.

The loose documents (articles, speeches, photographs, legal documents etc.) are of primary interest to me. I have been given a mandate to create a web-based, revenue generating distribution system for people to purchase archived copies of this material. Here's an example of how this might play out, at least in my mind :)  

1. Customer uses keywords to search our website for articles, court cases etc.
2. Search uncovers content Customer is willing to purchase
3. Customer goes through the buying process (create user/pass, verify info, complete payment etc.)
4. Once payment has cleared, Customer downloads document

That's it. Very simple, right?  Yeah.... right.

Here is where I need advice...
* Best Practices related to scanning/archiving all manner of documents (I will be using a Fujitsu fi-5750C w/ onboard VRS Professional)
* Creation of a secure, searchable archive used to categorize, sub-categorize and cross-reference thousands of documents, photos etc.
* Electronic delivery method of files to Customers
* Prevention of unauthorized duplication (impossible task, but still...)

Any feedback, experience or advice you can provide would be greatly appreciated.

Thanks in advance,
Kabe

PS - EE indicates I am "Advanced" in this area. I am not. :(