I just use the alt key and the number keypad-- Not the numbers above the letters on the keyboard!

no insert-- (they look good on my screen)--but incase they don't for every one...
Alt 167=º (degree symbol)
Alt 175=» (double arrow head)
Alt 172=¼ (1/4)
Alt 171=½ (1/2)
Alt 162=ó (accented o)
Alt 164=ñ (n accected with ~)
Alt 165=Ñ (capital N with ~)
Alt 155=¢ (cents size)
Alt 156=£ (English Pound)
Alt 157=¥ (Yen symbol)
Alt 145=æ (a e ligiture)
Alt 146=Æ (capital A E ligiture)

Part of the problem/solution is how your email system handles character sets-- the answer is buried in the HELP-- for your email system..

One of my "tasks" was publishing a list of common symbols-- but for work, these included degree symbol, lots of arrows, lots of spanish (alt 168=¿)-- but trade mark, copyright, and Registered are not much in demand...