Can't get special characters on my keyboard?

My laptop keyboard does not allow me to use the alt + number combinations I need to get the special characters (accents and such) for Spanish. This MAY be related to the fact that the number pad doesn't work. I bought this laptop used, and I think something might have been spilled on that side of the keyboard. But I don't get why the combinations don't work with the number row at the top of the alpha keys. I hope to be able to get the laptop repaired soon, but in the meantime, any work-arounds?

Thanks!