I use a combination of things...
For paper receipts, I've got a manilla folder I just stuff them into. I haven't organized them or anything yet. At some point I might scan them and do that, or I might not...
For things that I order online, I've got a separate email folder that I move all the order confirmations, email receipts, etc. into.
We use Quicken for managing all our household finances, so whenever I record something in Quicken I put a "tag" on the transaction that says "GTO" so I can pull everything together into one report if I want to. I just went into Quicken and did that - had it total everything that was tagged. Whoa!
I knew it was a big number, but it was a little sobering to see it in black and white.
I've got a separate folder for other documents, like installation instructions, specs, and etc. that I want to keep but that don't have anything to do with a financial record.
For a project record, I use a free photo web-page builder doo-dad called PhotoOnWeb. I got it here: Online Photo Sharing, Picture Sharing, Share Photos, Photo Share
It's pretty easy to use. It comes with some basic web-page templates that you can customize and save as a photoonweb "project document" and then publish out to a web server. Updating it is easy... you just open the project document, drag new photos into it, add captions, then re-publish out to the server.
My site is here:
My 1969 Pontiac GTO Restoration Project - Personalized photo album in html with PhotoOnWeb by VSO