Just use a graphics program like Photoshop or Irfanview to create a small image with the text
yourname@youremail.com, save it as a transparent GIF file, and use that image in place of your anchor text.
Your code will then look like this:
< a href="mailto:yourname@youremail.com">< img src="http://www.yourdomain.com/image.gif" border="0" alt="whatever you like here">< /a>
Note: I've added spaces after the open brackets < above to display the code.