As you will note when you check out page 90 of the Sederer and Dickey outcomes book, permission to use the SCL-90-R is required from NCS. However, sometimes errors are made, and my curiosity was peaked, so I called NCS for clarification. The customer service person stated quite emphatically that in order to use this research tool, permission to use must be granted by NCS. I asked if it would be ok if I copied the SCL-90-R from a colleague to use in my own study, and she said that that is prohibited by copyright law. that is pretty clear to me.
of course, people do use measures all the time without consideration of "permission to use". I, for one, am not inclined to enter into this type of practice, and wouldn't recommend it to anyone else.
However, perhaps there is a grey area here that I am not familiar with. Further discussion may be enlightening. meantime, I would recommend getting permission, since apparently there is no fee (as Sederer and Dickey suggest), and all you do is pay for the test forms and for whatever scoring you want NCS to do for you, or for the scoring forms and software.
hope this is helpful.