Yellow teeth?

i have naturally stained teeth and they are quite yellow. i am very slef conciece of them. i dodnt wnat to ahve anhthing actually done...but i was wondering if there were any ways to bleach/ whiten them that work.....i ahve tried a few products but i am a little impatient and they dodnt seem to be working. is there something that i could buy/ an at home remedy that works?