Pricing is something that I have had asked a lot lately and so I wanted to address this issue.
Of course, pricing is going to depend on the type of SEO "white hat" or 'black hat", how comprehensive it is to perform what the client expects and the quality of what part of the
"SEO Pie" they are working on. Ex. Link Building
So, I am going to include the links to answers to these questions - I found in MOZ.com.
http://moz.com/community/q/2011-sseo-pricing-costs-what-should-you-charge-how-much-should-you-pay
https://www.google.com/url?q=http://moz.com/blog/seo-pricing-costs-of-services&sa=U&ei=38nyUtbLBY34oATs3oFI&ved=0CAYQFjAA&client=internal-uds-cse&usg=AFQjCNGYyM9x80i-OmBPFzUODxTb9IfOFw
http://moz.com/ugc/what-to-charge-for-seo-and-inbound-marketing-services-14703
I hope this is helpful.
Brook