pmoore, my DS is 7 weeks and has just had his second cold .
I have used the saline drops and they really help. Also after checking with GP I have used Olbas oil on a tissue, and when really bad disolved a small teaspoon of vapour rub in boiling water - however this does make your eyes stream so dont put it close to your DD.
Also a wet tea towel over the radiator moistens the air at night which helps. Also put DD in the bathroom while you shower/bath as the steam helps.
Medised can be used from 3 months and can aid breathing too - but it depends on whether you want to give her medicine yet, regardless of the age thing.
But I agree with you - roll on spring!
My DS actualy could'nt breathe at all last weekend after I took him to a local park and fed him, I thought fresh air would help, but not when windy. He started throwing his head around as he could'nt breath in! On instinct I ended up tried to suck the blockage, but that did'nt help so I had to blow it down instead otherwise I dont think he would be here this week!
It truly is terryifying when they are so small!