I am not sure if this answer could help you but you don't really need a Spanish keyboard. As a Spanish speaker I can tell you, there is no need to have a Spanish keyboard, it is easy to find the Spanish letters such as ñ or even these ones é ó á (you just hold the letter for around 3 seconds and options will appear on screen) I know some other Spanish speaker who also own Macs and the have the regular keyboard.
Keyboards are available for almost all the languages in the world. I often use a Greek keyboard to write in Greek. It takes about 3 seconds to change the keyboard (with the approipriate accents) in the language you desire. You can select the keyboard in the system preferences.