Wondering if there is an accessory for my golf cart to carry my putter.

Why not in the golf bag? I have seen putters in 2" PVC tubing so you just can carry the putter by itself but I just keep mine in the bag and then carry it to the green. Am I missing something here?

I have a ball picker-upper thing that when I put it in the bag it gets caught and comes off in the bottom of the bag.

I am sure if you enquire at the pro shop of your golf community, they will be more than happy to answer your questions, instruct you as needed, and assist you with any accessories available... at a cost of course.

You do have a club house don't you? No cappy type thingy for your ball picker upper?

I have one too, I put the scoop end up. Originally you said "putter".