A great website to start with is The Environmental Working Group (which is also a great resource for MANY of the issues I am learning about).
They have a specific part of their site dedicate to organic produce, and I learned a ton from their comprehensive list...The Full List. I printed this list and then highlighted the items we consume the most of and created my two lists...
My Needs to Change Priority List, ones in bold we have already switched...
My Thank-Goodness List (these are low in pesticides, and we eat them a lot)
I also signed up so I could download the Dirty Dozen, Clean 15 Guide in a smaller format, that I can carry in my wallet when I am shopping.
Another resource I used in determining which items to switch first I found here-5 Easy Ways to go Organic. On this list we have already switched milk, peanut butter, and ketchup.
I also learned a lot form this article from Dr. Greene's website-Organic ~ A Choice for Our Children.
I plan to extensively research my shopping options in my area to locate where to get the best organic produce at the best prices. Cost is a very important factor for our family, so I need to be responsible.