The best solution for creating an Ecommerce store in WordPress, in my opinion, is to use WP E-Commerce.
There is a good tutorial to get you up and running:
http://www.1stwebdesigner.com/tutorials/create-e-commerce-websites-wordpress/
*UPDATE* PHPurchase seems to be a serious contender to WP E-Commerce, with some users saying that it is already better than WP E-Commerce. So I suggest giving it some consideration as well before making your choice.
WordPress ecommerce shop Themes
Crafty Cart V2.0 (integrates with WP Ecommerce) – Free
Shopperpress (theme + shopping cart)
Markettheme (theme + shoppping cart)
SimpleCartJS (v2 exists but not ported to WordPress)
WordPress ecommerce Plugins
Further reading
http://mondaybynoon.com/2010/08/09/wordpress-custom-post-types-phpurchase-cart-part-1/
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Web professional in Malta, Europe. Focusing on building visually stunning websites that are easy to maintain, usually using WordPress as the CMS. Web developing since 1995, loving WordPress for more than 5 years.
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