The battle is already lost. The best way to find things is to formulate a strategy before you start filing them. By narrowing down the search area, or having better info to key on, standard search tools will work fine.
1. Have a folder structure with some logical categories
2. Have meaningful filenames or add some sort of suffix string to the filename
3. Add keywords in applications/databases where that is possible.
Basically you need a document control system, without which almost nothing would ever get built in the real world.
Taking a silly example, if you sell stuff and sort documents by alphabetical customer name, it's not too difficult to find Mr Smith, he's under "S".
I guess someone will have to sit down and figure out if it is worth/feasible doing something about the problem.
Starman*