Unless things have changed, I do not believe you need any permission to create a tutorial. That said, I remember when I ran Ventura Software, we had over fifty books in print at one point about our product. We were happy about most, but a few were nothing more than a re-do of our user manual (not plagiarized, but the same information). Thus, a person could copy our disks and buy the book for $30 and avoid paying the street price of $500.

So, if you want the cooperation of the parent company, try to do something different from what they already do. Usually, the company is eager to cooperate. In Sony's case, I know they have done all sorts of things with Spot, although I don't know whether this help has been as freely extended to others. Their marketing group seems very strange to me (from a distance; I haven't actually met any of them).