http://thefacelessorder.com/
This guild on Live caught my eye actually.
They are a progression based guild on Test server. Test works as if you have a subscription, but is completely free. Downside being its down more often than normal servers and they can patch stuff on there that is broken.
You can get to level 50-60 really quick on live and join them if raiding is your thing.
If you are absolutely not a raider and prefer grouping, P99 for you IMO.