MSDS Collection Script

We need a program that can crawl the Internet looking for material safety data sheets. We are looking for the easiest, quickest way of doing this. Many of the sites use javascript that must be gone through before obtaining MSDS, some require you to enter keywords before listing them out. Some provide .DOC files, some provide HTML formatted documents, most provide PDFs. The program will not be considered working unless it is able to obtain at least 1,000,000 data sheets of unique products on the web. There are literally tens of millions such sheets floating around the web right now.