There is some type of organizer from Adobe that is free to download and use. I can't remember the exact name of it, Adobe Album or something like that. I have it and tried it. It's on my computer at home and I'd have to wait until this evening when I'm on the computer, but I will look to post what it is.
It is something similar to Picassa (also free).
I personally don't like the way organizers work. I like to physically move the photos and organize them in a windows explorer type interface. I use thumbnail viewer type software for this and have Thumbsplus. There is also Irfanview which is another excellent completely free program. They run much like WinExplorer. Of course, if you shoot RAW, that is different as I don't know if these thumbnail viewers handle RAW (doubtful). I come from the experience of not having the capability of RAW in my camera.
I just wouldn't do any editing with the thumbnail viewers. I have tested resizing and resaving a copy of the same original photo in Thumbsplus, Irfanview, PaintShop Pro, and Photoshop. PaintShop Pro and Photoshop resized much better quality images than the thumbnail viewers. PaintShop Pro is an excellent cheaper alternative to Photoshop for photo development, editing, and manipulation. As good as PaintShop Pro is (excellent), Photoshop exceeds it by a very large margin in that the tools are much easier to understand and use.
I've never tried Gimp (free). I will some day just to try it out. I'd also like to try out Photoshop Elements, but haven't downloaded it yet.