This hexadecimal conversion site is really handy. I can browse all my character sets and, as long as I have a unicode number for it, I can pull up the numeric character reference for an html and/or xml document. Like I know the difference.
Simply plug the unicode number in the Convert field and click the TO DECIMAL button. The result is the numeric value that you can use with
nnn;. The "n" represent the numeric decimal value for the character. (ex. ö) which is 246. Also, if you want the hexadecimal equivalent, for reasons I'm not too clear on yet, then plug the decimal number into the Convert field and press the TO HEXADECIMAL button. The result is the value you can use for the same character using this format:
nnn;. (ex. ö)