I still consider myself just barely above a beginner, but it looks like I have unlocked four of the eleven bonus songs in RS2014.

 

Disonaur - Sea to Swallow - 2013

Matt Montgomery, Brain McCune, Brendan West - On Top Of The World - 2013

Playground Kings - Self Trap - 2007

Verses Them - Impossible Dreams - 2013

 

I know I'll never get most of the missions completed, so I'm not sure how many more of these songs I'll get.

It doesn't bother me as I can find better songs at CF than most of these RS bonus songs.

Here's some more info on the RS bonus songs.  http://www.theriffrepeater.com/the-bonus-songs-of-rocksmith-2014/

um what bonus songs? haha Shows how much I know when I play. 

I unlocked all of the songs fairly quickly by first playing all the songs in my library once and then some of them again on score attack mode. No missions involved. Don't know what is it that actually triggers the unlocking of stuff.