Add a custom font

Hi, is there anyway I can add a custom font to the font drop down lists that appear in the theme options?

I’ve tried adding this to my child theme css file but with no luck.

@font-face { font-family: ‘rough_typewriter’;
src: url(‘http://www.mywebsite.com/fonts/rough_typewriter.eot’);
src: url(‘http://www.mywebsite.com/fonts/rough_typewriter.eot?#iefix’) format(’embedded-opentype’),
url(‘http://www.mywebsite.com/fonts/rough_typewriter.woff’) format(‘woff’),
url(‘http://www.mywebsite.com/fonts/rough_typewriter.svg’) format(‘svg’);
font-weight: normal;
font-style: normal; }

.sf-menu {font-family: ‘rough_typewriter’;}

Any ideas. Many Thanks.