door speakers

I own a 99 C5 and my drivers side speaker rattles as if it is blown. Any suggestions on how to be sure and where can i buy a replacement.

I thought my speaker was rattling too, but most of the time it's that little Bose emblem on the speaker cover. You might want to make sure that its not that first, because if it is then all you have to do is put a little double sided tape on it and problem fixed.