We turned off our water main, but water is still trickling out of the toilet supply hose. What next?

You have turned off the fresh supply line but every pipe in your home is still full of water. If you need to stop the drip then drain the house from the lowest fixture or outside spigot.

The valve at main shut off is leaking. U either have to replace the washer in valve or replace the valve.

If this is city water, have to shut off supply at curb/street.

What is reason for having water feeding toilet disconnected?

If just want to fix toilet valve, open a faucet that is closer to supply and it will drain the lines. U will be able to repair toilet valve.

Chuck