Have you ever seen those chars with names like ÇÉL? Well this is how they do it. They use letters called Extended Ascii Characters, and all you have to do is find the letter you like from this chart:
and hold ALT and punch in the numbers ON THE NUMBERPAD! (numbers on right side of keyboard) you see in front of the letter than you want, like ALT+128 = Ç and ALT+144 = É. If a GM sees this they may or may not make you change your name, depends on luck, I have seen level 60s with names like this.