As your interested in the statistical side of punting my experience has been that Malcolm Knowles of inracing is invaluable here.

Alternatively you could purchase a reasonably priced data base such as "RACE CENSUS"( advertised on this site )and run as many bits of "what Ifs"through that.Its a hell of a lot of fun and explodes many of the punting myths that plague the industry.

Cheers.
darky.