If you want to go to work for a firm,go to them first. They'll probably supply you with study materials for free or a reasonable charge. You will be under pressure to prepare for the exam in a timely manner,however. If it were me, I'd buy the series 7 manual or check out some of these links on this thread and study at home first. Most manuals come with several practice exams. After I pass the practice exams,then I'd go to the firm. As far as taking the exam goes,it's no big deal. You sit in a room in front of a computer that has a touch screen. After selecting A,B,C or D as your answer,the computer pops-up the next question, and so on. I don't remember exactly,but I think you have to get at least 70 percent(might have been 80). If you fail, I think you have to wait 60 days or so to take it again. Don't take the test to lightly. People will tell you it's a no-brainer,etc. Alot of people from my group didn't pass. Hope this helps. Good Luck!
When my brother joined the firm he went to ebay and bought used books and a CD to help him test...made a 95 on the exam and saved some bucks too compared with new! He later told me he sold them back on ebay for what he paid! Just a little tip from the boys at ECHOtrade... Good Luck!