It can be a long haul to reach the point that you can work full time as an affiliate. Particularly if you want to learn on the cheap, you would probably want to do a couple of hours in the evening after your regular job.
Bear in mind, affiliate marketing is a business, not a job, there's no guaranteed pay check for a weeks work, in fact if using PPC sort of paid traffic you can expect to loose money for a time, while prospecting for a winning ad-product combination. Spending some money on instructional material might actually save money by shortening the initial fumbling around period, which causes many frustrated would be affiliates to quit before seeing a profit.
You might be able to find some 2nd tier instructional video on cickbank that's a rehash of the big gurus advise for around $20, I find it helpful to look over someone's shoulder at first.
Search the web for affiliate forum, you should be able to find discussions by people in the trenches, while affiliate oriented blogs will offer helpful free articles, you can find lots of tutorial information on using adwords ppc on the google web site, though google is making it tougher for affiliates, who they view as unneeded street hustlers.