No ferry, just a couple of small airlines. I am sure you could find a DM on Curacao but the shore diving is no big deal, in many ways it's easier on Curacao than Bonaire. You can stay very shallow if you like and still see lots of life. You could use the dive bus for your first couple of dives then go on your own......on the other hand for airfare and a place to sleep I would be happy to DM for free. 
