WebCTO Tested the following FAQ plugins:

http://wp-answers.com/

http://wordpress.org/extend/plugins/q-and-a/

http://wordpress.org/extend/plugins/dynamic-faqs/

http://wordpress.org/extend/plugins/qa/

http://wordpress.org/extend/plugins/question-and-answer-forum/

WebCTO recommends

 http://tribulant.com/plugins/view/8/wordpress-faq-plugin 

Shortcode for Tribulant WordPress FAQ Plugin:

Groups List – this will display all the FAQ groups

[wpfaqgroups]
 

All Questions – display a list of all your questions

[wpfaqs order="DESC" orderby="modified"]
 

Search Box – a search box will be added on the post/page you insert this shortcode into

[wpfaqsearch menu=1 group_id=X]
 

Ask Box – an ask box will be added to the post/page you insert this into

[wpfaqask group_id=X]

Read more: http://docs.tribulant.com/wordpress-faq-plugin/508