If you want to successfully mine useful data from your web logs, you should carefully instrument your websites. Garbage in, Garbage out. Parameters in the URL can be easily mined, but they should be standardized across all your websites or properties. This will simplify the Business and Customer Intelligence mining process and increase accuracy.
Somethings to Track:
1. Page Views
2. User Session
3. Click Through Path
4. Entry, Exit pages
5. External Reference Views
6. IP addresses - > Reverse lookup general location of user
7. Page mapping to business owner
8. Logical Page Groupings
9. Hosting Servers and their Geographical Locations, if your distributed
10. Original Web log File that this information came from
11. Passthrough parameters to be further processed and mined by the business specific to a given website.