Max - here's another thing to keep in mind. A lot of what is posted here on the Ranch (especially in the
SCJP forum) was originally written by someone else so you've got a couple layers of copyright here...
Take Dan Chisholm's mock exams, for example. He created a lot of mock questions and they are all copyrighted under his nate, on
his site. Quite often, people post his work in the SCJP forum. That content, originally posted under Dan's copyright is now posted under JavaRanch copyright, as well.
The good news is that folks like Dan don't get very bent out of shape about people reposting their work elsewhere. Of course, the people doing the posting aren't generally trying to say that this is "their work," either. It's obvious that it came from someone else, even if they don't say so explicitly (although we prefer it when they do).
The whole idea of taking information posted in the SCJP forum, which may have come from other, now untraceable sources, leads to some hairy copyright issues. I'm no lawyer, but it looks like a mess I wouldn't want to get involved in. If you want to grab the "best of the best" mock exam questions, I'd suggest trying to contact some of the mock exam makers out there directly. Perhaps you could contact Dan Chisholm or Marcus Green. I don't know how keen they'll be on handing out their copyright to someone else, though - it's their hard work and has, in some cases, turned into a source of revenue for them. I would sincerely ask that, if you do decide to contact these folks, you repsect their decisions. Just remember, they put a lot of time and effort into what they've accomplished.
And, certainly, if you go through with this, I would suggest that you clearly state where questions came from so that due credit can be given.
There are my two cents, anyway. Feel free to disagree as you see fit.