The link below has the best plants I have seen lately. It's family owned and operated since 1945. I just found them a few years ago. I believe they have a good rating on Garden Watchdog, also. I like the berries named after Indian tribes from the Arkansas Fruit Experiment Farm. These are the latest and best of the thornless blackberries as far as I know.

Here is a link that might be useful: Simmons Berry Farm

Fall Gold raspberries have done really well for me, for, 15 years or so? They're avilable from a lot of places, including, possibly, some of your gardening friends & neighbors. I have abundant starts every year that have to be removed from the patch to keep it in check.
They start producing in July & continue until frost (or you get tired of picking them). The flavor is ambrosial, the color ripe peach.