A good exercise to begin with is using the Wizard or Sportsman racing papers and profiling individual horses .
The Wizard is only available online from everyrace but contains more racing information than the Sportsman.

i.e Fav distances
How they perform over various track conditions
Weight carried in successes or failures
How they perform with individual riders
etc etc etc

I would concentrate on Class horses normally weighted from 56 Kg and upwards.

Cheers.
darky.