When producers require extras and walk-ons for a production they approach one of the many specialist agencies and may also advertise in the local press.
We can't recommend any specific companies but suggest you use industry publications for advice e.g. the one published by Spotlight at www.spotlightcd.com*.
*This link will take you to a website outside bbc.co.uk. The BBC is not responsible for content on external sites.
If this did not answer your question, please advise what information you would expect to be provided.
© 2013
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