Accented letters are easy under GNU/Linux or OBSD under X. Just launch:

    setxkbmap -us option ctrl:swapcaps -option compose:rwin 

The first switch switches ctrl with caps lock (it helps your hands) and the last one maps the right Windows key (you can use menu key from laptop too with compose:menu) so you just type [ ' ] [ a ] and you'll get an á char.