Well, I don't have a tip for organizing files, but this is a little something that I find helpful when posting to the Gallery. I made up a worksheet that I keep track of everything I use on a LO so that when I post to the gallery I have all the info. This is especially helpful when I've taken items from numerous sources. I print it out in "landscape" mode so I can put the info for 3 LO's on each sheet.
This is the info I included: date, name of the forum, name of the challenge, name of the page, template, kits used, fonts, individual items used - papers, elements.
I find it especially helpful if I post a LO on more than one forum.