If you are still interested, you can buy this stuff at WalMart called The Works toilet bowl cleaner. It gets out every stain. Shut off the water and flush, then add the cleaner. But, you don't need to, it works great with water in the bowl. I use gloves when I clean with this stuff, it has some type of acid in it.
If you want something more earth and person-friendly, take Coca-Cola, in 2 liter bottles, drain all the water out of the bowl. Get as much water out as you can! Fill the bowl up with the Coke, making sure you cover the stains you want to remove. I used to fill it up to the rim, because that's where I had problems, with rust stains. Let it soak, the longer the better. Then flush, and the stains will be gone. Usually an hour or two will do it. Coke cleans a lot of stuff, believe it or not!
at 9:24 PM on Jun. 16, 2011