The neti pot can be a really nice alternative, or augmentation, to cold medications. When I feel a cold coming on, and throughout, I use the neti pot every morning until my nose has stopped running and the cold has passed. Except in extreme conditions, I manage to avoid having to take a any medication at all. That being said, when I get a cold so bad that I can't breathe when I lie down, I'll take a NiQuil so I can sleep!
There are plastic neti pots out there, I've seen them at the drug store, however my neti pot is ceramic. I like that it can be sanitized with boiling water and washed in the dishwasher. I buy the salt to make a saline solution in bulk from Selsi Sea Rosks at the St. Lawrence market.
In combination with my homemade handkerchiefs, it's my zero waste way to deal with a cold.