Hello everyone,
In the past I've written a few tutorials, all kinda small in size. Now I'm thinking about the possibility of writing much longer and more advanced tutorials, but right now I'm unemployed so I thought I could do it all more in-depth and detailed, and make it commercial.
It'd all be based on UnrealScript so the best format would be written and with images at the side. Making a video tutorial for this is out of the question.

About the topics - They'd be centered around game saving/loading, inventory and items. I'd start off with the basic Sapitu implementation and then my own extension of it, which are all needed for my own implementation of an inventory system.

The first question would be: is there enough public for this to be worth it? I know for a fact that at least a few people would be interested (I've been asked to write a tutorial about my inventory implementation), but I don't want to do such a big effort to reach only 4 or 5 guys with this.
So this is also a call to anyone that has ever created a tutorial, commercial or free (best if someone has created both!), or even a book, to throw here their experience with the results. is it worth it, based on the public reception? comment and rant away!

And the second question: what's the best medium for this? digital or printed book?
if digital, do I need to code my own website with a user authentication and payments system (that'd be overkill!), or is there some site where I can sell this kind of stuff? (I only know Eat3D in regards to commercial tutorials, and it's not some sort of marketplace where anyone can sell)
what about a printed book? I know only a few UDK-related books have been published and people have asked for more. Is this a possibility at all?

I'm trying to get all of this straight to decide if it'd be a good idea or not. As I said I'm unemployed (save for a small website-upgrade project I'm about to finish) so I need to invest my time wisely