Train & bus travel Alicante -Madrid-Sevilla

I've never booked a long-distance bus icket in Spain before the same day (usually 30 mins before), and never had any problem.

Hi all,

I haven't had many responses to this thread. Might it have been buried somewhere? I'd really appreciate your input on this. If for some reason the original info doesn't show up, here is what I'd asked:

We are travelling from Alicante to Madrid, and later from Madrid to Sevilla, both in mid-July. I was wondering if we needed to book our train or bus tickets ahead of time, or could we do it once we're there. (We'll be arriving in Spain 10 days before needing to travel those routes.) Also, which is better - bus or train?

Thank you all!
Gibs