For immediate relief boil a pot of hot water, get a large towel. Place your face over pot with towel over your head and breath in thru your nose. Begin slowly as it will be hot, keep your distance at first to test the heat.
I also recommend a stop at the pharmacy for a sinus cleanse kit containing sodium chloride. I wonder if Iodine solution would be good for rinsing the sinuses??? Perhaps someone may chime in on this theory...