http://b2evolution.net/man/2004/06/16/evo_skins

That page will point you in the right direction. skins/yourskinname/_main.php is just xhtml with a few tags sprinkled around that make b2evo work.

That page has the general idea of evoskins, and this one is the Templates and Skins category in the manual.

http://b2evolution.net/man?catsel[]=97

Once you've had a stab, feel free to post any further questions.

Is that to change the skin of your blog? Because that's not what I want to do!

From what you said, it is. You want to make your blog look like the rest of your site, right? Well, make a skin that has all the needed bits (the posts loop and the archives) and pop all the rest of the gubbins from your site in there too. Make your blog the default through index.php (or rename stub_a.php to whatever you want to, change the blog number in it if it's pointing to the wrong one, and make the appropriate change in the blogs section of your backoffice), and no one will ever know the difference.

You could try :-
in config.php
change baseurl to http://www.louisesworld.co.uk
crack open skins/custom/main
delete everything apart from the bit that shows the posts
in index.php (for phpnuke)
include "b2evo directory/index.php"; // where you want the posts/comments to appear

?

Thanks I'll try that! :D