Agents get information about auditions for roles, either directly from casting directors (CDs) and producers or from an insiders-only fax service called "the breakdowns." The breakdowns is a daily faxed list of roles being cast, and they are available only to agents and managers. There are those enterprising actors who get together in groups and outfox breakdowns into giving them a subscription, but actors are technically not allowed to get breakdowns. But we have no qualms about giving you the website:

SoYouWanna know more? Check out our full-length article SYW get a talent agent?