Excellent resource page on the summary of Caching
One of the tools that I use extensively in troubleshooting is HttpWatch. I highly reccomend this tool if you need to see what is going on with the browser. I like Fiddler as well, however, with HttpWatch, I do not have to do anything special in set up, click the button and start capturing the information I need. Yes, Fiddler is Free, but sometimes a little change goes a long way.
