Drew, there may be some good suggestions for cab savs already in this thread, but if you want to start with a quality wine at a reasonable price, the Robert Mondavi Woodbrige cab is around $13 Cdn (so less USD) and excellent for its price. Another good cab standard is Wolf Blass Yellow Label. They are big sellers, popular, but they are lovely quality performers for their price.
Painter Bridge is a Californian zin that is similarly priced and quite lovely.

Best cab i've had yet to date, a 1994 Lindemans Coonawarra. Hard to find now.

"Those who preach the myths of audio are ignorant of truth."