I'd just write down the notes with pen and paper. Definitely would not pay for a program to take notes with- how frivolous. If you want them in electronic form you can copy your notes as a way of studying.
What he said. High-tech solutions can often be great, but don't overlook the tried and true. Pen and paper give you a lot more flexibility than any software application can (after all, most of them try to emulate what you can already do with pen and paper).
Before I became a full-time researcher, I taught undergraduate history courses. It always seemed that students with laptops were busy focussing on their computer screens rather than me and what I was trying to teach. The notepad students would jot down a few lines and then pay full attention again. That's the most effective way to learn, I believe. Laptops in the classroom are a distraction for students.
Also, as miles mentioned, re-typing, cleaning up, and consolidating your notes can be a very good way to review.