I'm working on a tough web site debugging issue, and somebody sent me the below link to Tess's blog. It is the best debug blog I've ever seen.
If broken it is, fix it you should
There are other good debugging reosurces.
http://www.charlescarroll.com/chaz/site/4302/default.aspx and http://www.charlescarroll.com/chaz/site/4810/default.aspx have many others in addition to Tess's blog.