We just went through some privacy and illegal issues with our landlord before we moved... I'm pretty sure in every state, they have to give notice if they or anyone hired by them, has to inspect inside or outside for any reason. Here's the thing... She owns the house, but the minute she turns the dwelling over to you and accepts your money, she has to abide by the law just like you do, and you have your own set of.rights as a paying tenant. If its not specifically stated in the lease and agreed and signed on by both parties, her little drive-bys and consequent notices are most definitely harrassment.
Check your state's specific tenant rights and landlord laws, but I would definitely request an incident report from the responding officer!