So maybe I'm a little late, but wanted to share a quick n' dirty way to do this:
<a href="javascript:var d=document,f='http://www.facebook.com/share',l=d.location,e=encodeURIComponent,p='.php?src=bm&v=4&i=1326899080&u='+e(l.href)+'&t='+e(d.title);1;try{if (!/^(..)?facebook.[^.]$/.test(l.host))throw(0);share_internal_bookmarklet(p)}catch(z) {a=function() {if (!window.open(f+'r'+p,'sharer','toolbar=0,status=0,resizable=1,width=626,height=436'))l.href=f+p};if (/Firefox/.test(navigator.userAgent))setTimeout(a,0);else{a()}}void(0)">
LIKE THIS (or <img> tag)
</a>
This uses older code and is not related to a FB App so it doesn't put Insights into your FB account, but to help spread products it works fine.
I literally copy/paste the above code into the Product Details Template at the bottom in the Social section
<a href="javascript:var d=document,f='http://www.facebook.com/share',l=d.location,e=encodeURIComponent,p='.php?src=bm&v=4&i=1326899080&u='+e(l.href)+'&t='+e(d.title);1;try{if (!/^(..)?facebook.[^.]$/.test(l.host))throw(0);share_internal_bookmarklet(p)}catch(z) {a=function() {if (!window.open(f+'r'+p,'sharer','toolbar=0,status=0,resizable=1,width=626,height=436'))l.href=f+p};if (/Firefox/.test(navigator.userAgent))setTimeout(a,0);else{a()}}void(0)">
LIKE THIS (or <img> tag)
</a>
This uses older code and is not related to a FB App so it doesn't put Insights into your FB account, but to help spread products it works fine.
I literally copy/paste the above code into the Product Details Template at the bottom in the Social section