Doesn't sound like a headgasket at all to me. Does the smoke smell like coolant? If your headgasket is anywhere as bad as mine was you would definetly smell coolant. Also, when I would first start my car in the morning it would idle like it had a cam and puff tons of white smoke until it warmed up. You said you dont have coolant in your oil or oil in your coolant. Once again, when my headgasket went bad I had alot of oil in my coolant, ecspecially in my overflow, and I was going through a ton of coolant. Try draining your oil and look for gray crab, looking on your dipstick doesn't always do it.
But from what you are describing, it sounds like valve seals. Does it smoke much on the top end or just the bottom end?.....of your RPM's that is.
If it is your headgasket, have fun, it took me a full weekend to do by myself, and with some help from Ace$nyper with removing the old gasket. And don't expect a new head to fix it either, could still be piston rings.