Tracking individual Referrers / grouping referrer stats

I have been trialling the system for the past 3 weeks and am pleased with the product. The viewing of on line information is extremely interesting and I have the following suggestion.
Many of the referrers^? I am using require payments, either for banners, placements or pay per click but I have never had the capability of tracking results by referrer^?. I would find it extremely useful to have a profile built of these referrers showing number of visitors, average time spent on the site, average number of pages visited. There would possibly be a few more categories but this would then start to provide some real value as to the worth of the referrers.