As has been observed above in this thread, you have to be a very smart consumer when choosing olive oils. There are lots of oils on the market that appear to be Italian or Spanish but in reality are made up of a blend of cheap oils from other countries. It doesn't mean the oil is no good, but be aware of where the oil actually comes from, not just what country it was packed in.
We use quite a lot of olive oil at our house so I am always looking for good deals on high quality oils. My favorite origin for olive oil at present come from Lebanon. One brand is called Saifan, packed by Said Saifan in Amyoun Koura, Lebanon. The other is called Mid East El-Koura Extra Virgin Olive Oil, Imported by Kradjian Importing Co., Glendale CA. Both of these are sold in 3 liter glass bottles. They are both very nice quality and relatively affordable. They typically sell for about $20-23 for 3 liters. The flavor of these oils is quite good, with that typical green flavor and the small "catch" in the throat that tells you it has lots of the stuff that keeps you healthy. These are everyday working oils, not the super rare type oils that you will pay $30 for just a small bottle. I buy these at Wholesome Choice market in Irvine, CA, but I imagine these or similar brands are available in many stores that specialize in Middle Eastern foods. For me the quality of the Lebanese oil is much higher than most comparably priced Italian or Spanish oils.
I've also had good luck with Greek olive oils. You can get some really nice quality Greek oils for not to much money, especially those coming from Crete. I don't remember specific brands at the moment though.
Finally, Trader Joe's sells a Spanish olive oil under their own brand that costs about $8 for a liter, and it's a very nice oil for the money.