Lots of the Indian stores also have good prices on EVOO. If you catch a sale you can often find first press for $13 for 3 liters. The little Persian store on Coit & Parker in Plano has a great many oils and normally had something for the $13 range. They also carry really good oils for a pretty decent price compared to other stores.
You know, some of the larger Middle Eastern grocery stores in Dallas have excellent values on 3 litre cans of olive oil. The oils originate from Morocco and Lebanon, etc. But are very good. They tend to be a bit darker and stronger than the Spanish, Greek and Italian oils but, otherwise very good and, much more reasonably priced. It depends really on what style of olive oil you're looking for.
This is an easy one for me. Jimmy's Food Store at Bryan and Fitzugh for the largest selection of Italian EVOO in 3 litre cans at much better prices than Central Market. Or, Costco for the absolute lowest prices for 3 litre cans of Kirkland (their own brand) EVOO and Philippo Berio. I think they carry Bertolli as well.
The very best prices on 3 litre cans of pomace olive oil is at Jimmy's. Pomace olive oil is the type of olive oil used in most Italian restaurants because of it's low price and "neutral" flavor. It's like a third pressing of whatever is left after the "virgin' and subsequent pressings. Don't hold me to it but I think a 3 litre can is around $15.00. It's Great for cooking!
I've also bought one litre bottles of (store brand) EVOO at Sunflower Market on Henderson for as low as $4.99 when on sale. It's usually $5-6.99 for a one litre bottle. It's quite good, too! Comparable with Wholefood's at $9.99.
Jimmy's Food Store
4901 Bryan St, Dallas, TX