Your question is not unreasonable at all. Now, I don't own a netbook, nor have I used one so bear that in mind, but...
You mention Skype. If you can access the internet and download and install new software on the netbook, I don't see any reason why Skype or any other voice-enabled software wouldn't work on a netbook. Now I don't KNOW for certain whether you can install new software on a netbook. I'm assuming you can.
I already have Skype for my Windows Mobile cell phone. I can use it to chat or make free calls. (I don't use it for calls because, technically, it violates the terms of service for my cell phone contract - and most of my cell phone calls are basically free anyway.)
So, you would need to find out whether you can install software on your netbook. You'd also need to find out if it has a microphone or a jack for one and you'd need to check your terms of service.
However, I don't see any technical reason that you couldn't use your netbook to talk. It just wouldn't be your standard cell phone call. It would be over a VOIP chat program.
I hope this helps.