Its not where its from. It's WHAT it's from.

When it comes to wine, many of us less educated, tend to think it's all in the label. Now how do I know if this wine, that I've never heard of, is good or bad. Dining out, do want to risk $40 on a bottle that I might not like? Simple answer to that would - NO. Having said that, what makes a wine good? This all very basic stuff, mind you. Every now and then, we come across an ad on TV, see a great picture of a glorious-looking bottle on the side of a bus or someone comes along with "Oh, you need to try that wine!". I, personally, tend to disagree with all of these.
It's not where it comes from. I've had bad Shiraz from the Barossa. Bad Semillon from the Hunter and categorically bad wine from Bordeaux. It's WHAT it comes from. the soil, the climate, the grapes, the people. Small unknown wineries come up with ground-shattering wines every now and then. How? Better soil. Better climate. Fantastic people, who love what they're doing, make their own rules and not report into managers sitting in a high-rise sending emails to justify their existence in the million-dollar companies. 
BUT. Again, how do you know? You'll need to get hold of a good wine-book. There are many, you'll get to know which one is good for you, in time. Campbell Mattinson - most red wines in Australia. James Halliday - most wines in Australia. Robert Parker - most wines in the US and rest of the world. Or you can join an online forum. Or just do your research on the net. If you like something, get in touch with the wineries. Trust me, they are the nicest people out there and would answer most of your question to the best of their abilities.
Dining out? This is tricky. Most places do not tell you anything about their wines other than WHERE they come from and how much they cost. Not good enough. Ask for a tasting. Or just ask the staff what they think of it - again, risky. The best thing is to have your research done and have an idea of what might work for you. If a place has a wine-list that tells you a bit more about the wine, like tasting notes, that'll help a great deal.
Bio-dyanamic wine is always a better way to go if you're lost. Because its a perfect example of 'WHAT it comes from'. 
Enjoy.