blog pulled for resource abuse; where to find problematic scripts

My host, 100megshosting.com, pulled my blog yesterday for ‘resource abuse.’ They say that I have a rogue script but won’t otherwise narrow down the issue. They gave me back very limited access.

I did two things (based on their suggestion) that did not solve the problem:

1) update to the latest version of WP;
2) remove the plugins I installed recently.

I thought I was pretty savvy at running my WP blog, but I am in way over my head and need some plain English step-by-step help to finding that rogue script.

Thanks,

Rae