PLEASE HELP ! Can`t see ringtones, songs or apps?

I have been using iTunes for the last year without any problem. Last week without any message/warning a problem started untill today. I have synced my iPhone with new ringtones,songs and apps, which i can see in the latest iTunes but are missing in my iphone 3GS v5.0.1 32GB. I have synced several time without sucess. I have done no change in itunes or on my iphone. I have tried to convert new ringtones, or download them directly from specified ringtone websites but no luck. I have also try reauthorize my account but nothing. At this point sync is useless because it doesnt even save the apps that i download from the AppStore application in my iphone, plus when i try to use iTunes to download any app it goes straight to the iphone without storing it first in my pc. HELP PLEASE!!!