If you are using AdWords but can’t see the SEO vs PPC traffic go to your AdWords campaign ‘My Account’ tab, click on ‘Account Preferences’ and then enable ‘Auto tagging’ under ‘Tracking’.
A problem is that, for some reason, you will still get PPC keyword data attributed to your ‘organic’ traffic. This seems to be a bug and not a widely reported one. However you can get a much better overall picture of your spend and traffic trends.
