May I offer my services as a beta tester, when you are ready?
Some tools exist, but no one (as far as I know) has yet made a good research manager for genealogy research.
The program GenSmarts will analyze a file, and will let you make comments about what you've found or not found, and make notes, and you can generate work lists specific to a library you want to visit, or a website you want to search -- but it doesn't include logging.
And like the Research Manager module in Ancestral Quest, or a to do list with a Named List in Family Historian, the items are tied to people in your database, which can lead the user to decide a source belongs to a particular individual ahead of the evidence.
Paper systems exist for keeping track of research, some of them in chart form (for example, there are nicely-designed forms in the workbook accompanying Emily Anne Croom's
Unpuzzling Your Past) -- I had thought about trying to port those to Excel, in the same way that the person who did Census Tools has made spreadsheet versions of census forms -- but I've never made the time to do that.
http://censustools.com/
http://www.unpuzzling.com/books.php
I make Excel spreadsheets all the time when I am working out problems -- then I forget what I named the file, or what directory they ended up in -- so when I need to go back, I end up starting all over. [oops] A good research manager that worked with FH would be so useful.
But to get back on topic -- I do like Sarah's idea, especially if it were done as Gerry suggested, with a stand-alone program along the lines of Gedcom Census.
One of the things I like about GC as a stand-alone module is that it allows the user (if proper care is taken to save files in the right way) to work with both programs open at once. That would probably come in handy while getting one's report in order, too.
P.S. to Sarah -- boo for the ninja edit -- it is absolutely unfair to take away your idea while I am busily writing away posting that I liked it. [smile]