South African Chenin can be good, too. Ken Forrester is a reliable producer with good US distribution. Kim Crawford is a good name to look for on bottles from New Zealand.
This has already been mentioned, but there's good value in South American reds, particularly Malbec. Try Kaiken Ultra (their cabernet under the same label is also good), Santa Ema's higher-end Amplus bottlings, Catena Alta, La Posta. Most in the $15-$20 range. Clos de los Siete is an excellent Argentinian blend that seems to be quite widely available.
Cheers!