I've been running it all day today with a USB stick for the receiver.
I agree that there is a LOT of information spread all over the place out there and that makes it confusing as all heck but once you get it working, it ends up being pretty easy.
I think I was lucky and happened to stumble across a site right away that basically laid it all out for me including links to the sites with the software needed.
It actually works very well but now I'm hooked and looking at getting a much better receiver than the USB sticks offer.
The USB sticks are a good way to see what is up and how things work though plus you can use them for other things and not just planeplotter but that was my main interest.
Like kma371 said, post what you have or what you are looking at and someone will help you out.
I think my first link on this very subject actually came from a user here and then I became hooked but I do remember all to well at how frustrated I was with all links I found and what seemed to be an endless amount of instructions!
It turned out all I needed was the correct SDR stick which I had already. That part is important if that is what you are going to use.
They are cheap and can be had for about $20 bucks off ebay.
I think the main seller goes by the name of noelec. His stuff can be bought cheap and he spells it out in his auctions if the particular stick you are looking at will work with planeplotter.
He will also help you get it going. I know he sent me an email with the basic instructions for setting everything up and then offered his full support if I had any problems. I never did need to contact him though.
There are a LOT of people into this aspect of the radio hobby so don't give up! I'm sure many here will lend you a hand if needed.
I've also used my usb stick tuner to fully track and monitor a local 800 MHz trunked system so they can be used for a lot more than just planeplotter. I have so many receivers though that I really did not need another one for trunking but I just had to see if it would work and it did!
And pretty well at that figuring I just hooked the thing to the tiny little 4 inch antenna that came with it. That little antenna works ok for local stuff and even the 1090 MHz frequency that is used for aircraft.
A dedicated 1090 receiver is much better though from what I've read and seen examples of but for $20 dollars and some of my time, the usb stick route has been well worth my time and 20 bucks!
And that includes the frustration of sorting through all the websites on the subject.
I know there are sites out there that are easier to read and skip the stuff you don't really need to get it working with planeplotter.
It's worth it though and especially when you pickup your first plane overhead.
My setup is only good for maybe 75 to 100 miles out but I have tons of local traffic as I'm only about three air miles from a major airport so that helps. I still cannot pickup aircraft until they are about 5,000 feet altitude or higher though. I can darn near see them on my weather camera before my little usb stick starts hearing them!
I'd imagine the power level the aircraft use for sending the data is pretty low. I've never bothered reading up on it beyong getting my setup up and running almost a year ago now.
If anyone reading this knows what the typical Mode S or AC transmitter power output is from an aircraft, please let me know!
I do get great reception from all types of aircraft passing over my airspace at altitudes of 10,000 feet and above. Most that are just passing through seem to be held between 30,000 and 40,000 feet which is plenty high enough that the local airport can operate without worry.
I do wish more of them broadcast position data though as I like watching the display of planeplotter when it does show actual position of what is flying overhead.