I found the following tea mixture to relieve the symptoms of sinusitis: add 1 tablespoon pureed ginger root, 1 tablespoon dried nettle leaf, 1 tablespoon rooibos tea, and crush a stick of cinnamon (optional; for flavor -- it covers up the flavor of the nettle leaf which isn't bad, but isn't good either) to a 10 ounce tea pot. Bring water to a hard boil and pour on the tea. Let steep 10 minutes. Tastes good sweetened with honey, though I prefer it just spicy not sweet. Drink 1-2 times a day, for example in the morning and evening. I usually only have it in the morning, but I find it works better twice a day for bad symptoms.
For ginger puree, I usually buy a bunch when it's a good price at the farmer's market or Asian grocery, puree it a food processor, and freeze it in 1 tablespoon balls. It keeps well in the freezer. For dried nettle leaf, I look for it at a cheap price in the tea shop or health food store. I've seen it at Fred Meyers, though it was too expensive. I prefer loose leaf. I also bought rooibos in loose leaf from a tea shop.