I know the basics of Spanish, but would like to learn to speak it more proficiently. I feel that improved Spanish will help me to advance in my career.

I have a fairly long commute - 1 hour each way on the train - and thought that would be a good use of my time to study on the train.

Can anyone recommend a good product - book, cd or both - to teach myself Spanish?

I heard the Rosetta Stone is the best.
Rosetta Stone: Store
I have no idea though---never tried it.

Thanks. I have heard good things about it and am going to give it a try.