Ok here it is....
1.) If you mind is set on getting into a finger tip ball get a power grove, tornado, tropical storm...Hard surface reactives, easy to control easy to maintain.
2.) MAKE SURE YOUR PROSHOP OPERATOR FITS YOU CORRECTLY!!!!!!!You can't out bowl a bad fit.
3.) This is the most important, go see a coach. You don't have to go every week, or for hours at a time, just take one day go see someone and get some tips. Make sure to take notes. A good coach will have some sort of literature with pics to help you get the hang of things.
I am sorry to hear that you are throwing the ball without a thumb. Despite a couple of international guys have done VERY, VERY well not using a thumb and utilizing the "two hand delivery", I have to advise against it. It will cause timing and consistence issues later on as your game develops.