no need to apologize in fact I'm sorry for getting so technical, I didn't pay close enough attention and assumed you were already using sitefinity... so let me give you a quick rundown, and let me know if I go to fast or skip any details!
sitefinity uses templates to render things like blog posts and post lists. by default, the system uses embedded templates so you don't have to do any configuration out of the box to get started. however if you want to change the layout of your posts, or add customizations, then you can download the templates for the specific area (blog post, post list, etc) and make your changes, and tell the system to point to your template instead of the embedded one...
that being said, it would be trivial to download the template, add your code to say the bottom or top of a blog post so that it shows up on every post... however if you want to be able to put in code a-la wordpress, it's not so straightforward, but I can try and help you come up with a solution, but will involve programming in asp.net
the simplest way I can think of is to handle the page_load event and search the blog text for your meta code and replace it with adsense code...
something like below, where Content is the label that holds the body of your blog. Sitefinity will automatically populate this with your blog text before loading the page, so you can then modify it with your changes afterwards...
at least I'm pretty sure this is how it works, any one from sitefinity team care to confirm this can be done?
string const adsensecode = "your code here";
protected void Page_Load(object sender, EventArgs e)
Content.Text = Content.Text.Replace("[yourmetacode]", adsensecode);