Storage Management/Auditing

For lack of a better place to query, and a distinct lack of findings in 
my last few hours of googling, I was hoping someone on the list might 
be able to enlighten me on the subject of storage system management and 
auditing.

I'm currently admining a low load, high capacity storage array (Raid 5, 
1.4TB) and am interested in being able to quickly determine activity 
(file addition, deletion, etc), file system usage, and any other 
relevant information regarding the array. I have already covered the 
hardware status (via 3ware monitoring tools) but have no way beyond df 
/ du of checking usage and changes (which is tedious and shrinks in 
practicality as the file system grows).

I was thinking that I could possibly use AIDE to track the changes, but 
then again the current port is broken (sending email to maintainer 
concurrently) so I thought I'd look for a better solution.

Any suggestions would be helpful. Thanks.

-John