monitoring user processes

[Steven Day <scd104 ecs soton ac uk>]

Hi, firstly my apologies if this has been asked before, but I have
searched the lists to no avail, so I assume it hasn't. 

For my dissertation project I am trying to use some machine learning
techniques to improve simple HCI factors of the traditional desktop, my
project is to produce an application that can 'intelligently' suggest
applications, files, contacts etc that are relevant to the current
situation of the user. I won't go into the exact details of that because
my question is somewhat more basic, though if anyone is interested I
would be happy to fill them in more on my ideas. My intial problem
however is how to collect the information I need to make these
suggestions. 

For example, I am planning to use the functionality of inotify to
monitor document access/creation etc in a user's home directory, and I
would like a similar method for to monitor the execution of applications
by the user. Ideally I'd like a notification system like inotify is for
files, but with notifications of programs being executed or completing
their execution. Does any such system exist? 

In my research of the gnome system and associated libraries so far I
have only come up with the option of polling top repeatedly and
filtering the output in some way to remove system processes from the
results. 
D-Bus also seemed to have potential, but I cannot find anything in the
documentation about this kind of functionality. Have I missed something
in the gnome environment that would give me the information I want? 

Thanks for any help in advance.