After Detecting Click Fraud Then What?

I have recently been a victim of click fraud on this past sunday. I have informed google and overture. I am
using clicktracks and AwStats. Here is my plan,

1. I have a list of IP addresses that had sunday as there last visit. I will analyze these IP adresses for large amounts of visits with small amounts of pages and hits.

2. I will note these. Then using clicktracks, find the IP addreses with the quickest visits which also used the PPC words in question.

3. The problem is there are 517 visitors from sunday. I tried to open my raw logs but the file is 1 gig and I can't open the whole file.

4. So what do you think, Any ideas? Any tricks? I have noticed a large amount of visitors from the virginia area? should I find what competitors are in virginia?

5. My client is already reluctant to run these campaigns? How do I try and explain what is going on? Any experience with this?
I have paused both campaigns. should I turn them on and monitor closely?

Thanks Everyone for you thoughts,
Brad

I guess it just isn't the best place to ask questions anymore? I have asked a few questions and PPC just gets ignored...

Thanks B

I cant open the log i a lame excuse ....

if your using UNIX just cat LOGS.txt | grep DATE
if you are using windows system just split the file
go to google.com write in the search BOX
"Split FILE" utils
you can download somthing like 200k utils that will split the files to 5 MB
i can open 5mb without a problem so tell me how things work out .