Upload & Sell: On
As mentioned, how you organize is a personal thing. The use of Lightroom is not relevant to this. You should have the files organized in a logical way, independent of the application. Although the camera based structure Alan described works for some, for most it just complicates things. LR does not care what camera you use.
LR has powerful search functions that allow you to search by date, camera, lens, keyword, and many other metadata fields. However, I want my folder and naming convention to allow me to find the pictures of my daughters 21st birthday without the use of any software assistance besides the disk organization. All software goes obsolete eventually and you can be certain that the new one will not be compatible with whatever you had before.
For me, I have a mixture of family events, Landscape day trips, etc, arranged as follows: One catalog, a folder for the decade, folder for year, within each year a folder for each shoot that is named with the month-day-event "02-27-New-York-vacation". I also rename the files, but the name describes the event and ends with the camera generated number