i go to microsoft word and insert the symbol i want, then paste it here. hehe
actually, you can use character map in windows too, or experiment with Alt - Numpad Keys (a list can be found in the shortcut keys for character map/MS word symbols)
for example,
Alt - 6 - 5 - 4 gives me Ä
Alt - 6 - 4 - 5 gives me à
Alt - 9 - 5 - 1 gives me ?
be sure to keep your numlock key on so you don't activate unnecessary commands like Home, PageUp, PageDown, End, Insert.
if u're more interested, google for character map