Well said, Big Mike.
I never give out my RAW files - only high resolution JPEGs.
My profits arent generated from print sales, in most instances. With that being said, I charge $35-$45/file or $300-$400 for all of them.
Now, when I sell digital files I have them sign an agreement and make sure they fully understand that they are not allowed to edit, crop or do anything to alter the image(s). Then, I explain that if they decide to get large enlargements (11x14 and larger) that I would recommend they have them done through me so I can ensure a professional quality. Because we all know if someone takes a file and gives it to Target to print (on high glossy paper) it looks like poo. Small prints are do-able.
But thats just me. Like Mike said, make sure you charge to make up the difference from the lost print sales.