Newbie Question/Advice Please?

[JewelSki]

Hi All,

Im new to Wordpress and looking to have a blog with shop,, I have looked at the themes here and then I looked through the Showcase section and really love the things that can be done with these themes,, I notice some have shops,,, I would be very grateful if someone could please let me know how I would go about having a shop included in one of these theme like the ones in the showcase?

Also is buying a theme and including a shopping cart something that can be done rather easy or is it something I would most definitely have to pay a designer/developer to set up for me?

One more thing, if I buy a theme, does it come with the XML file so when installed it looks like the demo, and are there tutorials to show how to set everything all up?

Thank you in advance, really like the look of a lot of themes here :)