For folks that have a personal profile (a “standard” account), you can use a clever trick to invite all of these friends to fan the page.  There is no way to automatically import.  When you’re on the Facebook fan page that you want to invite all your friends too, you hit “suggest to friends” under your profile picture and then paste this code into the address bar to automatically select everyone:

javascript:elms=document.getElementById(‘friends’).getElementsByTagName(‘li’);for(var fid in elms){if(typeof elms[fid] === ‘object’){[fid]);}}

If you have thousands of friends, like I do, then this will save you hours each time.