Authors Victoria Strauss and A.C. Crispin give you some tips on what to look for when you're viewing an agent's website. This is especially relevant if you don't find the agent on the How to Pitch guide, nobody you know has heard of him or her and Google is giving you nada.

WHAT YOU SHOULD SEE:

A list of recently published books.

The name(s) of the agent(s) and information about their background.

WARNING SIGNS:

No sales.

Unverifiable sales claims.

A claim that sales information is "confidential".

A client list unaccompanied by information about published books.

No information on who's running the agency.

Spelling mistakes, typos, grammatical errors.

Ignorant and/or silly statements.

More here.