I've scoured around and haven't been able to find any kind of a decent reference guide on Visual Studio property sheets. Most of what you can do with them cannot be done through the UI, so I've got to think there is a reference guide somewhere that can be useful in understanding the available fields, syntax, etc.
Lunicon's answer to this question was really useful, but I'd really like to know where the information on what could be done in property sheets came from. I'm hoping it was not a lot of trial and error. ;)