My husband and I have used a variety of methods to self-teach. Pimsleur, podcasts, studying grammar books, and All Talk CD listening tapes. We are experience language learners and have found that learning on our own is actually more productive than a class if you are motivated to keep at it, and get to a point where it is part of your regular schedule (I do it while in car and while exercising mostly). We've studied Mandarin and Spanish this way. I also have studied German, French and Greek in the past. I do have some Hubs on learning Chinese for kids and adults.