Is there much of a difference between organic vs. regular olive oil?
Olive oil degrades over time so freshness is important.  Some of the higher priced olive oils sit on shelves for a very long time and by time they are sold they can be of lower quality than some mass produced olive oils.

I'd say you're in the right frame of mind and would recommend finding a brand with a local representative who can trust and know the source and timing of the oil.  

Many smaller olive oil producers don't bother with organic certification because of cost, but they have same or better standards.  Therefore there is a sweet-spot where you can get quality olive oil similar to organics at decent prices.

Keep in mind good olive oil is produced in many places, including Greece, Spain, and Lebanon.  Not just Italy.