I am just at work to recieve NOAA-18 in about an hour.
But i am using an common VHF/UHF radioscanner.
First you have to know which sattellite is when over you head, under linux i am using gPredict
each NOAA sat has its own frequency somewhere between 137.000 and 138.000
there is an software called "WXtoIMG" which just grab the sound of the reciever (anyway if FCD or mic input)
the software includes a very helpfull help-function which describes everything verry clearly.
I hope this helps you a little bit
73 Michael