Hi, Jill,

My dog was having ongoing uti and my holistic vet put her on:
1) Shilintong Tablets http://www.opane.com/kidstonshile.html
2) Cranberry extract available at your HFS

I've also heard drinking more water will help.  If you have any oriental stores 
near you see if they have the tablets there.  My local store charges about $8 a 
bottle.  Kept her on them for over 6 months and so far she's been fine.  

Take care,

Cindy