Literary agents www.writers-publish.com suggests to search for them at the relevant literary events such as writers conferences, write them directly or some contacts of yours may recommend you someone appropriate.
www.LiteraryAgents.org
http://www.bookpublishingagent.com/
and
www.FictionAddition.net
may be right places to start looking from.
There is also internet-resource http://www.guidetoliteraryagents.com/ with lists of agents and practical advice for dealing with them.
In www.writer-publish.com it is advised to check carefully the list of works that the agent arranged to be published, not to sign contract until checked by your solicitor and to be careful with agents charging upfront fees for reading your work.
Also, the estimate fee of literary agents is said there to be at the level of 10-15% with any expenses to be charged separately. Ideally the agent should be a member of the Association of Authors’ Representatives www.aar-online.org, but Scott Hoffmann in his article “Is your agent legit?”on http://www.writersdigest.com/ considers this factor as non-decisive so far as quality of services is concerned, provided that good references are in place.
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