Classicist's Online Library

The links go to e-books at the Internet Archive.
You might gave to sign-up for a FREE account, to read them. 

• Greek and Roman sport : a dictionary of athletes and events from the eighth century B.C. to the third century A.D. / Matz
• Sport in Greece and Rome / Harris 
• Arete: Greek Sports from Ancient Sources

• Cruelty and Civilization: the Roman Games / August