I want to be able to monitor cellular and cordless phones using a scanner
device that attaches to my PC. Can you tell me what is available and what
frequency range I need to search to listen?

FYI - I'm an old 80's scanning hobbyist back when I believe the waves were
more free and I used to capture cells on the 800 MHz, and cordless phones on
the 40 or 48 MHz ranges, from what I remember. With all the newer
frequencies since then such as 900 Mghz, 2.4 and 5 GHz ranges, I'm a bit out
of date as to how capable we are of capturing these frequencies today. I'm
also inquisitive as to what my wireless laptop devices are capable of, since
I have a 2.GHz router (transmitter?) and laptop wireless card (receiver?). I
wonder if these can be utilized for scanning as well. Can you tell me where
the ranges fall for cordless and cell phones today, and if there exists such
a device to scan using PC hardware and software? If you can guide me to a
updated lesson on the web, I'd appreciate that too.