Check out the Performance Box (Vbox) website, at the bottom they have a section title "Area's of Interest", download their ebook on circuit driving. It's a fantastic read, with different driving lines shown, circuits and video's with their telemetry.

I'm a big fan of data collection and can be done cheaper than a Vbox. Though their software/interface is sensational and probably worth the price for its ease of use. You do need an external GPS, a phone GPS isn't sufficient, but can be had for quite reasonable money if you're wanting to run it through your phone. Check out Harry's Lap timer as an example, but there are others. I run a GTech Fanatic RR GPS and gopro camera's, which I than pull together in RaceRender.

Happy to elaborate how I use this info to reflect and improve on my driving. There is also a thread in this section (motorsport) on some of things I've done/learnt with this data.