We haven't got sick yet this season [knock on wood]. But I got fully stocked up with all the things I like before the season kicked-off.
For the adults. Netti pot. Netti pot. Netti pot. My husband who has the most contact with the outside world has not been sick yet. He does his Netti pot every day after work. Our salt is 1/2 non-iodized salt and 1/2 baking soda with some essential oils mixed in (tto and rosemary to be exact).
We also diffuse therapeutic grade essential oils in our home when ever anyone comes over who might have "new germs." Check out diffuser world and ebay for ultrasonic diffusers that can run off 20 drops of oil all day. We usually diffuse Young Living Thieves oil or their Purification. Both smell delicious!
For the drugs we take I bought a ton of Occilococcinum (I'm sure I spelled it wrong) which I read is kind of like a homeopathic version of Tamiflu. We also use echinacea (angustifolia is stronger than purprea) whenever I remember it. B&T makes an EXCELLENT cough syrup (it's honey based so not for babies under 1) called Cough & Bronchial Syrup. It's short lived, about 4 hours for my kids, so we usually have to re-dose in the middle of the night. For stuffy nose we really just use the saline drops and the bulb syringe and we always use a humidifier.
Also, the not so natural. Whenever we go to the store we wipe the cart down with those sanitizing wipes. As soon as we get in the car we have everybody slather on the Germ-X hand sanitizer that we keep in the car. And the second we walk in the door we all wash hands. Also make sure you sanitize the stuff in your house often (We use Merlin's Magic homemade Lysol) - phone, switches, doorknobs, kitchen/bath cabinet handles, remotes, toys, etc.