I just did this, if you’re somewhat comfortable with editing HTML it’s not that hard.
Not sure if the changes would remain if you do a theme update, but you could always add it back in.
Add this to the header.php file where you want the linkedin link to go. I put it at the end of the list.
<dd><a class="linkedin" href="https://www.linkedin.com/in/your_account_name" target="_blank">LinkedIn</a></dd>
I also added this to the styles.css file, so the icon would show up.
You can find a 16×16 icon for linkedin on the web and upload it to the ‘images’ folder within the theme.
#follow dd a.linkedin { padding-left: 21px; background: url(images/linkedin-icon.png) no-repeat 0 .19em; }
