I see a lot of 4-digit codes, but I use ALT 167 for º and ALT 164 for ñ using the 10-digit keypad (no leading zero). I also sometimes use the Character Map, as Kirk suggests, using select and copy/paste, so © and ® and ¼½¾► and many more are available. And, with character map, you can read off the ALT+ code for a given character for future use, if you wish.