OPI is the best.
You also have like Revlon, ChinaGlaze, UrbanDecay, Essie.
Maybelline has a nice range of colours too.
Answer mine?
http://answers.yahoo.com/question/index;_ylt=AvxaiJU5I.BMlG9sEmxkISHsy6IX;_ylv=3?qid=20111009073815AA8jeUt
http://answers.yahoo.com/question/index;_ylt=ApY91SeR9PiGwtE42OoVUIXsy6IX;_ylv=3?qid=20111009072526AAZnHrd