I have heard good things about Pimsleur, our own government uses it to train their people, but it is pricey.
You can find used copies of the program on ebay for much less, though.
We used Pimsler, before our trip to France/Italy....several years ago.
Very helpful.
You can maybe find in your local library. They usually have the Spanish at least. Pimsleur gave me a head start to my government mandarin course.