In Google Blogger Statistics, only the top 10 referring sites are shown as below. As bots take over and with referral spam this feature is completely useless. Google should do a better job of handling the Statistics feature.
Checking the server log files for statistics of a self hosted blog is also a bit difficult because of the spam. It would be a good to have `reliable regularly updated publicly accessible list of spam sites`, which can be integrated with a script to get useful data out of the server logs.
Edit: Looks like Google Analytics is doing a good job of filtering the bots.