What I want is get an object from an API with a HTTP (eg, jQuery\'s AJAX) request to an external api. How do I start? I did research on Mr Google but I can\'t find anything
You just want to call an external URL and use the results? PHP does this out of the box, if we're talking about a simple GET request to something serving JSON:
$json = json_decode(file_get_contents('http://host.com/api/stuff/1'), true);
If you want to do a post request, it's a little harder but there's loads of examples how to do this with curl.
So I guess the question is; what exactly do you want?