www.popsoda.com
Go there, order Coke and Dr. Pepper made with good old fashioned cane sugar, in Mexico and Europe.
They have every soda you remembered, but can't find anymore, its an amazing place. You can order anything to be shipped, or if you live in Phoenix, go in and grab what you like, they also have tasty root beer in kegs.
I like Coca Cola Light (aka Diet Coke) from other countries.
Check your local supermarket. Coke is coming out with a new product "Coca Cola Zero" by the end of the month.
I have heard they sell them in the Mexican marts around here. I am going to grab a couple.