What's the best product for removing cat urine from carpet?

We recently moved our family 1200 miles and our elderly Maine coon has taken to peeing on the carpet in two places in the house. I'm working on addressing the peeing problem (which is difficult with older cats), and in the meantime I need a product that does a good job removing the urine stains and odor. I've been using Woolite Pet Oxygen and it removes the stain but doesn't completely take out the odor. The cat pee smell is lingering in the house so I have to smell that first thing when I walk in the door after working a 12 hour shift, and it's driving me insane. Does anyone know of a product that completely and permanently removes cat urine stains and odor?