I used Rosetta Stone at our local libary and really enjoyed it. We took a trip to French-speaking Africa and I wanted to at least learn the basics. I tried several different methods, from books on tape, online resources, etc, I would say Rosetta Stone was definately the best, because it helps you identify a picture with the word -- good if you are going to be doing a lot of speaking. If you need to learn the language for writing or reading purposes, it might not be as good.

Check your local library, because you may be able to use it free with your library card at the library. It might be a hassle to travel to the library, but think of it as taking a weekly class. I don't know what it runs, but I would say it's a good investment, because it's easy to use, effective, and encouraging.