There are two easy ways you can set up your computer for Spanish accents.

1.  You can go through your computer settings and set your keyboard up for US International.  This allows you to type accents easily when you need them using just the ' key and letter.  For example to make an "é" all you have to do is type ' + e and you'll get é.  The same for ó, to type ñ is ~ + n

Here's a link:

http://support.microsoft.com/kb/306560

2.  The other way to do this is if you're using Google Chrome you can download US International keyboard from the Chrome store and use ctrl + alt + letter to do accents.

Everybody, thanks for all your  detailed suggestions!

Normally you can use all the spanish accents with your normal keyboard. I have a "Belgian" keyboard and I can generate all the spanish accents. There are keyboard shortcuts:

For windows: http://symbolcodes.tlt.psu.edu/bylanguage/spanish.html

For Mac: http://spanish.about.com/od/writtenspanish/a/diacritical_mac.htm

Hope this helps

You can use a virtual keyboard, it provides you only the accents you need :

http://www.lexilogos.com/clavier/espanol.htm