They have been installing new wiring with grounds ever since I can remember. (Hint, I wasn't born yesterday...)
I have no idea why someone would build a house in 2004 and wire it with no grounds??? Do you mean a room addition or the entire house was built in 2004?
Anyway I have heard of some areas which have no electrical inspectors, thus people do not get electrical permits nor do they get their work inspected. Is this the case?
Permit or not, grounding is a good thing. It protects you and your family from being electrocuted.
I would suggest you get an electrician to check your main electric panel to be sure it is well grounded, then slowly begin installing new grounded circuits.
Then get a book on modern electrical wiring which includes the 2008 NEC requirements.
NEC codes nationwide...