I saw a couple of questions about charting and starting TTC this week on the boards, and I just happened to notice that the Fertility Friend e-book is free on Amazon right now: http://www.amazon.com/dp/B007IVNABU

I never actually read it (I read TCOYF) but I know a lot of people just relied on the FF tutorials, so I'm guessing this would be helpful. And more importantly, it's free right now (normally only $3 anyway). US/Canada only, it looks like.