hacking help

hay. i've looked all over the place on the internet, but i haven't been able to find any web sites to teach me how to hack, if anyone is willing to help me learn to hack, or find me a web site, please post here

Someone recently told me that you cannot link to proprietary libraries in GPL'ed code. Well, he might have been bullshitting around, but assuming he was correct I'd have to say: The moment a license restricts me from writing code the way I want to, it's no longer free, but a piece of shit.