The answer to all these questions is very simple, to me atleast.
By learning the methods of blackhats you can also fight back at blackhats.
Study from blackhat sites, blogs whatever you can find. It’s all about
vulnerabilities, like any other hacking or criminal stuff, these people are
always one step ahead. Otherwise it wouldnt exists.
I consider blackhats as pioneers. They search the vulnerabilities, and
other parties try to keep up fixing them. This is how we get bugs out
of systems, since no one spends time these days to test and make their
products perfect. Good example of this would be the movable type preview
button exploit, where one found out how to get backlinks from blogs, without
anyone else knowing about their existance… One also told that it wont work in
type 3.2/3.xx because of javascript, so now all you bloggers just go and update your
movable types.
What im trying to say here is that, these guys always come up with new methods, and there aint no one solution to fight them back. Instead you
should try to think it’s a good thing that there is so many of these guys, trying to
be better than other and go out and brag about it, so other people can fix or fight back.