Coming from a .net background so bear with me!
Does php have anything like a web.config or a global.asax file or is it simply dropping the application in the file system and boom it is running on the web server? (obviously dropping the files mapped in apache for the domain etc).
Specifically thinking of setting up wordpress.
Just drop the files ;-)
Of course, you'll need to have created the database (and db user), set up the Apache's VirtualHost, and you'll have to configure the application itself...
... But there is no notion of "application server" in PHP+Apache.
About wordpress, there should be some file explaining how to install, btw ; but it's not harder than dropping the files, maybe creating the configuration one, and a couple of "next" screens ;-)
PHP is a parser itself. It is not a framework. In ASP.NET, it is a Framework and thus it has its own config files.
As for PHP, we have php.ini - the PHP configuration that sets how PHP behaves and so on.
However for application level, you can create your own configuration file. Normally if you use a PHP framework, they will have an application level configuration file (eg. "config.php") which will decide how the framework will work and so on.
Wordpress installation is quite simple.