We did have a table of prices but found that each job was so individual that this was not even useful as a guide.
Whether your site is small or large,
Your ambitions for your website,
Is your site a CMS or a dynamic etc for instance,
Do we have to rebuild your site from scratch,
Do you want us to have daily input,
How large your sphere of influence is and therefore how many keywords or phrases are we opitimising for.
Basically if you have a five page minisite and want it to rival Yahoo we might be in for the long haul and this could be very expensive.
However if you wanted us to clean up your site and provide some one way links it would not cost so much.