If you are not seeing google (cpc) show up as a line item in All Traffic Sources in Analytics and you have an Adwords program running, then read on. And remember, Analytics and Adwords (at the time of writing) are two separate products.
Caveat: This becomes a bigger headache when you consult for many clients and want to have a centralized dashboard. You must then create multiple Google accounts. Ugh.
The creation is super basic. Simply follow the directions and a tracking code will be generated for you. Copy it and embed it in the conversion page of your site. Remember, Adwords and Analytics are different products. You must embed Analytics into your site as well but it goes into every page. With dynamic sites, usually in the template bottom or footer.
Embedding Adwords differs from site to site. Some users measure the ROI from forms, sign-ups, purchases, etc. Go to your developer or reference the e-commerce documentation on how best to do this. You can also contact me and I will try to help you.
Once this is done, you will be able to track conversions in Adwords and you will start seeing an e-commerce value associated with the google (cpc) line item in All Traffic Sources.
Last part, yes! Now you have the two products talking together and you can record the value of the Adwords from all sorts of dimensions. Now you just need some granular information on “each” transaction. I wrote up a whole article which explains how to build filters (regex) in Analytics.