Why isn't my music syncing from itunes to my ipod?
Can you play the songs on iTunes? The exclamation mark means iTunes can't find the file associated with that song. Maybe you moved it or it was deleted, or it lived on another hard drive. The solution is to locate the files for your songs first, and then either re-import them into iTunes or re-link them in iTunes. More information here: http://support.apple.com/kb/ts1408