This seems to have resolved my issue with looking at the reports I was interested in. I'm not sure anything has been getting logged. When I look at event logs under the Legacy Reports from the web interface I only show a couple dozen log entries for today and the next most recent entry is from April 2011. Obviously something changed in our environment at that time and was never caught. I'll keep an eye on the logs to make sure they are rotating properly. Thanks for all you help folks.