I just purchased a theme for a new design blog I want to set up from theme forest. I liked the look of it and thought I'd just customise a few things to suit. But now I've installed it it's basically just a skeleton with all the elements missing. I realise it's probably me being incredibly stupid due to having no experience with Wordpress but I'd like to just get it set up how it was when I saw it on theme forest. Is it possible to do that or is this just how all wordpress themes are?

Really depends on the theme you purchased. Many rely on widgetised areas. Have you got a link to your site?