... When it is a health issue and interupting others lives then its a problem. If a dog was roaming the neighborhood eating animals and pooping in others yards to the point where they had to change their lifestyles people would protest.
Bingo. To me it's not a case of liking cats or not liking cats; it's a case of one neighbor's pets wreaking havoc on another neighbor's health & garden.
The neighbor obviously doesn't plan to change her ways, and I don't see any alternative, Val, but to be very assertive about the situation. In addition to animal control, does your town have some sort of ombudsman or dispute mediator? In my opinion, you should use whatever resources you have at hand; germy cat poop in your yard and dead wild birds are issues that should be taken seriously by "the powers that be" in your town.