Hi Stuart,
This is just to give you some pointers, but a not a solution.
The first part of the code appears to be easy by looking at the log-in details of the site. The issue you face is once you are in, how to navigate to the right part of the page. It is really difficult for any one to give you how to get a data from a page with out seeing the format of the page. If a site requires a log-in details or intranet, you are almost left on your own. To scrape a data from a site requires looking at the source view of a page and this is can only be done by opening the page and look at the document.
If you look at the attached link, the OP had change the URL after he logged- on using his details.
http://www.domino.nrucfc.org/CFCApps/Financial/memsum.nsf/78342add422ca87a85256a0f004d46ff/" & Worksheets("Sheet1").Range("CoopID") _
This is the page (Which is different from the home page) where the data with in the document is found.
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