I aint got my Leon yet, but as far as i know, it should be on the fuel rail, as it is on other cars. The rail which your injectors are on, should have a valve on it, just like a tyre valve, probably with a plastic cap on it too. You can unscrew the plastic cap and push the pin in the middle with your nail, or a screwdriver or something, to test for fuel pressure. Beware for it squirting in your face though.
If i'm wrong, i'm sure soneone will correct me.