How to Study for an Amateur Radio License (U.S.A.)
This is my standard advice for how to study for the ham radio license exam(s).
There are 3 levels of ham license: Technician, General, and Amateur Extra.
Technician provides the least amount of frequency privilege, and Amateur Extra provides the most. When you take the license exam, you pay for the session, not per test. So, if you pass Technician, they will offer you the General test, and if you pass that, they will offer you the Amateur Extra test, all without having to pay any additional fee. The worst that can happen is you don't pass. But, you must pass them sequentially, meaning that the next level exam will not be offered until you pass the prior level.
I advise you to do like I did: use hamstudy.org in the (free) STUDY mode. Forget practice tests until you have done some studying. Just keep hitting the questions in Study mode. Why do it this way? Because it will tell you instantly if your answer is right or wrong. If wrong, you click the upper corner of the question and it will give you the full explanation. You need that immediate reinforcement, if you are going to learn. The practice tests don't give you an immediate correct or incorrect response.
As you go along answering questions, the site will keep track of, and display for you, the % of each category of question you have completed, AND how well you are scoring. This is cumulative. You can go back day after day, and it will keep your numbers.
Keep going until you have answered 100% of questions in all the categories. It is a known finite set of questions. Then, keep going some more to push your cumulative score up. You will know when you have the confidence to take the exam, but I suggest hitting 90% in your cumulative numbers.
Also get the ARRL books for each license tier (http://www.arrl.org/shop/
This is what I did, before and after work every day for about an hour, for 8 or 10 weeks. On the weekend, break up your studying into several shorter sessions. I first studied Technician questions, then started adding in General questions, while still hitting Technician questions, then added in Extra questions while still hitting Technician and General questions, and it proved to be a good strategy, because I passed the 3 exams in one testing session. I had zero prior electronics or related knowledge, and am no rocket surgeon, so if I can do it, you certainly can. You just have to study for it, and take the exams while it is all fresh in your mind.