Have you noticed how adverts follow you around the internet once you have been to an online store. This video tutorial shows you how to setup remarketing ads in google adwords.
Typically most e-commerce sites have one shared help page for returns policy, shipping details and terms and conditions. I have just seen the newly redesigned (again) ebuyer.com website and the help section gets in own drop down. They have broken down the help pages into 5 sections and then also a page for contacting them via a form, e-note and forums.
It allows your customer to get an answer to their query without searching for it, and gives the customer another reason to carry on the buying process.