Sorry, there isn't a nice answer to this Q. The best I can offer is: If the toilets plugged, call a plumber. If your more adventuristic here's what you can do: First thing is locate the water supply valve between the toilet tank and the wall or floor. Be ready to turn it off quick. Practice turning it off BEFORE the next step and you find out it won't turn. Flush the toilet. If it flushes ok, you can try some toilet paper to see if it goes down ok. If so, the bottle may have gone on down the drain. Next is: Put on gloves and reach into the toilet and feel for the bottle. Extract it if you can. Toilets have what's called a "Gooseneck" right behind the hole you can see. It's is shaped like an "S" so unless you want your neighbors to see the Fire Dept. pull your arm out of your toilet, DON'T STICK YOUR ARM IN AND GET IT STUCK! DON'T REACH ANY FARTHER IN THAN YOUR WRIST TO FEEL FOR THE BOTTLE. Extract it if it's there. Now comes the nasty part. You will need to remove the toilet to access the back side of the Gooseneck and the drain. There is a valve with a hose connected to it and the toilet tank on the side of the toilet. This is the water supply to the toilet. Turn it off. FLush the toilet holding down the lever to get as much water as you can get out of the tank. Remove the tank top. Use a rag and bucket to sop up the remaining water from inside the toilet tank and bowl. On the base on each side there is a 7/16 nut. Remove these. Get some newspaper or disposable drop cloth and spread it near the toilet. Now you have to lift the toilet off the holdown bolts and drain and set it aside. CAUTION: IT WILL BE HEAVY AND AWKWARD!! Now you'll see why you want to get as much water out as possible. When the toilet is removed you will be able to see directly down the drain and by tilting the toilet on it's side you will be able to see the other side of the Gooseneck. You may be able to remove the bottle now. If there is no standing water in the drain and you can't find the bottle it probably went on down the drain. If there is standing water in the pipe now is a good time to call that plumber. It gets more complicated and nasty from here.The good news is you have saved on labor cost by removing the toilet. You can also save on cost by re-installing the toilet. Be sure and clean the base of the toilet and drain face and use a new wax gasket and bolts. Good Luck.