Hey jplante4, that Freeze Alarm I linked to above (http://www.absoluteautomation.com/freeze-alarm-intermediate-model-fai/) does EXACTLY what you're looking for.
A lot of homes have a drain somewhere in the basement or crawl space that allows you to "gravity" drain the water lines. Just close the valve on the line coming into your home and open the drain, it should empty all water out of lines. Don't forget t...
I'm looking at this setup for my RV -http://www.absoluteautomation.com/cellular-freeze-alarm-kit/ - it'll let me have WiFi, plus I can use the little Temp. Sensor to monitor everything.