I was over in Seville a couple of weeks ago by car.
See my report on the drive on my blog here:
http://barlaventostravelblog.blogspot.com/2009/03/lagos-to-seville-again.html
As our Peugeot had just a an encounter with one of the new, rapidly expanding population of, jumping bollards of Lagos, (I was not driving at the time :) and I am sure it has nothing to do with the fact the brother of the Mayor of Lagos owns the local Peugeot dealership), I took a vehicle from Luzcar. They allow their vehicles to go into Spain as far as Seville with no problem at all and at no extra cost.. Tell them when you book you intend going to Spain.
On arrival in Seville, I suggest you park at the underground parking under the Bus Station at Plaza das Armas or at Cristobal Colon. From there on walk or use the TUSSAM bus service.
