Al, I use three different methods for freezing those herbs.
I usually use make my basil into pesto before freezing it. Then I freeze it in ice cube trays. However, I did find this web site that uses only basil and olive oil: http://kalynskitchen.blogspot.com/2006/06/how-to-freeze-fresh-basil-weekend-herb.html I would hazard a guess that it is the olive oil that keeps the basil from turning black as it did when I tried to freeze it by the following method.
For basil and parsley I chop the leaves in my food processor with some water. Then put--really pack--them in ice cube trays. Add water to fill and freeze. I keep some special just for herbs. To store them I go to the trouble to cut aluminum foil into strips (you can do several layers at once). Wrap these strips around each cube then I pack them into another square or rectangle plastic container that closes securely. This extra layer prevents freezer burn. I still have some that is four or five years old. Just putting them in a plastic bag they won't last very long due to freezer burn.