We're going to be doing a good deal of traveling around Spain in July and want to know what to expect with trains and buses. Which should we do? Are buses reliable? Cheaper? Do we need to buy bus tickets ahead of time? Train tickets?
We're going from Madrid<-->Toledo, Madrid-->Seville, and Seville-->Granada.
What would you recommend?

We are also going from Barcelona to Southern France, and are considering doing an overnight train. How are they? Is it worth it?

Thanks!
Adam