What I highly recomend for File Management is a programme called Directory Opus.
It's a replacement for Explorer like Photoshop is a replacement for Picassa. An incredible time saver. Wish I'd discovered it years ago. Probably the best programme I've ever used. Sadly not available for the Mac, which makes a Mac so slow to use in comparison as Finder is so cacky.http://nudel.dopus.com/opus9/
for a taster of what it can do - a very , very clever programme. The only down side is that it does so many things you have never used before you may miss features and setting up the preferences can take 30-40 mins as it's verrrry customisable. But you can always save your setiing and transfer to another computer no problem.
Lightroom is also very useful if only for one little feature, that is invaluable in cases like yours. It can import and sort into folders by date [the best way to manage your files anyway], though as it ignores movie, sound and some types of PSDs, don't assume it's got everything. So put al your files into one big folder and import in to another folder called say Images and then it will all be arranged by date.
I used LR to sort out a friends photo collection which iPhoto had scattered into lots of meaningless folders.
It's best to label the folder as well [2008-05-28 Motorshow, 2008-05-28 PR shoot, 2008-05-29 Wedding etc] and after a while you will associate shots with date, which is also handy with searching. I also put shoots into year, then month folders.
2008-01-1 New Year's Day hangover
2008-02-07 Dogwalk at Derwent
The benefit of this folder structure is that is it OS and programme independent, very, very important. So if you go to Mac or Linux to PC from Mac, or change the software you use to look at images as say Apple have replaced Aperture or Adobe go out of business, or you find something better it will always
work and always
Some screenshots showing the variety of ways you can use Directory Opus.
BTW I have a lot of hard drives!
I always laugh when Adobe claim a lack of resources when their software lacks features or is full of bugs as DOpus is done by two people and it really puts Bridge to shame.
You can trial it for 60 days, but it's worth every penny as it saves me so much time. Using Explorer or [spit] Finder is like running a marathon with your legs tied together in comparison.
Once you have sorted your files out, then
you can start with keywording as otherwise, it'll take 10 times as long.