My iTunes deleted all my playlists?

I have an ipod touch and i have bought music on it using the wifi, But i can't sync it on my itunes?

• I have bought music on my ipodtouch using wifi, but when i go to sync my songs it says "Are you sure you want to sync music? All existing songs and playists on the ipod will be replaced with the songs and playlists from your itunes library." My itunes was reset so all my songs had to be put back on my itunes but all my playlists were deleted. I had bought songs before and when i plugged in my ipod they would automatically sync on my itunes and into the playlist that i had selected .. while my itunes was being reset i was still buying songs on my ipodtouch...but now that my itunes is back the music that i have bought on my ipodtouch while it was down can't be loaded on untill i sync my ipod back on the itunes ...but my playlist that i used to have is gone....so i made another playlist but if i sync that it will take all the songs off my ipod and sync only the ones on my playlists...and my bought music will be deleted......please help!!!!!!!!!!!!!!!!!!!!!!!!

• Answer:

  i buy songs on my touch too, and when i connect it, it asks me to transfer purchases. if yours doesnt automatically ask you when connected, look in itunes on the file menus and on one of them should be transfer purchases.