Burning Oil/Exhaust Smoke

[BeckMule]

I know the topic of burning oil has been discussed ad nauseum, but I was hoping you could give me direction on my specific situation.

I have a 2005 4.4i non-Sport with 95,000 miles and have been adding oil at the rate of about two quarts per month. That's not a problem; I know these vehicles burn oil. The problem is, for the past several months I have been bowing out white (or blue/white) exhaust in copious amounts, particularly after the car has been idling. I passed mandatory emissions, but it's gotten so bad that strangers have flagged me down at stop lights to let me know how much smoke is coming out of the tailpipe. That has to stop; not only is it embarrassing, but soon the police will pull me over as well.

I know this problem may have a number of different causes, but I'm interested to know what it's likely to cost to diagnose and fix. I don't care if I need to continue to top off the oil; I am concerned only with the visible emissions. I will take it to an independent shop, not the dealer (I cannot DIY). I need to figure out of this is a problem worth fixing or if it's time to move on to a new vehicle. Thanks in advance for any input.