Here are some thing to think about when you set up an eCommerce site cheaply, and how to consider doing it:

1. Get a shopping site provider like Shopify.com. I will send you some of their competitors tomorrow so you can compare.
2. Sign up for your gmail account.
3. Once you get a site, you will need to sign up for:
a. Google Webmaster Central (For making sure your site is crawled by Google)
b. Google Analytics (for watching your site)
c. Google AdWords (For advertising)
d. Blogger account (for the blog)
e. Twitter/Facebook accounts for fan and discount pages.
f.  Set up a Yahoo Site Explorer site
g. Who will do you email marketing? (I recommend MailChimp for simplicity)
4. You will also have to consider the following:
a. What are you important keywords?
b. Who will write content for your blog?
c. How much can you spend on ads? Where and who do you want to target?