Lastnight I just noticed mold growing on the windowsill in my bathroom. Its not very much but I'm not sure how to take care of it? I've never dealt with mold. Can some one help. Thanks

Bleach or cleaners with bleach. Nutone/Broan make a humidity sensing bath exhaust fan.
Mold loves Dark and Damp.

I tried loads of things to get mould of the sealant on the bathroom sink. We are renting and obviously the person before didn't try cleaning very often so I'm talking about serious mould. I tried lots of different cleaning products even neat bleach but this one actually worked
Dettol Mould and Mildew remover

However from the way you spell mould I'm thinking you are probably american so might not be able to get hold of this so here's the active ingrediants - look for something which contains these :-
Less than 5% nonionic surfactant , Disinfectant, (Sodium Hypochlorite 2.5% w/w 25.9g/l), Perfume, Limonene

My moneys on the sodium hypochlorite being the 'right' kind of bleach to kill the annoying stuff.

Good luck!