Well if i was you i would go back into font book and make sure that your fonts are either on your computer or on your user, the only way i can see you doing this is by going into fontbook> preferences and then making sure that the defult location for the fonts is your user or your computer.
If that doesn't work try turning the fonts on and to do that you got to do this-
1.Double-click Font Book in the Finder, or choose Manage Fonts from the Action pop-up menu in the lower-left corner of the Font panel.
2.Select the fonts you want to turn on in the Font column.
3.Select an entire collection in the Collection column, or select individual fonts in the Font column.
4.Choose Edit > Enable Fonts or Edit > Enable Font Collections.
Sorry if that didn't help but i did try, font book isn't my special area after all

(P.S try looking on the help section of font book, that's where i got my answers from)