Godaddy for domain name: $12.99 USD, without a coupon code.
Hostgator: $.01 for the first month's service.
Wordpress as your CMS: Free
Total ~0.25 BTC
Sell one item within the first month, and you're able to pay for the second month's service at Hostgator. If you don't, pay the $8.95 USD out of your pocket. If no sales during the second month, close it down.
The other option is using the free wordpress.com as your CMS, with or without the blog aspect turned on, to garner a couple sales, coupled with proving that what you have to offer is viable.
How's that for magic?