I have a Windows 7 PC. How is it possible to get FM radio on my laptop?
I'll assume you are in USA - there are plenty of very cheap DVB-T + FM + DAB USB dongles (Realtek chipset) which with the right software, can also be run as "software defined radios" - the DVB-T TV standard is not compatible with USA (ATSC standard), but the FM should work. There are a few FM-only ones as well.
Alternatively, you need an internet connection and web radio player, for USA, this looks like a good selection .. http://www.america.fm/ - many will NOT play elsewhere due to regional restrictions
There used to be a product called RadioShark (made by Griffin Technology), which was a computer controlled FM receiver, and connected to the PC/Mac via USB, but it has long been discontinued and I'm not aware of any similar products out there.
So, if your PC does not have have a built in FM radio, your best bet is to find out if your favourite FM station(s) transmit over the internet and get an internet radio app (there are many available) and receive the trasmission that way.
You would need a cheap USB tv tuner card with AM/FM tuning capabilities. I don't know if there are any FM tuner cards still being made or supported since FM is not as widely used or in demand on a PC anymore. Once you install the TV/AM/FM tuner card and software, you can use Windows Media Center to tune the radio, just remember that you would need a cable/antenna connected to be able to receive the FM signals.
if you have radio receiver on your laptop, i think that you only need some app to start playing. if you don't have a radio receiver on your laptop then i suggest search online for your favorite radio station i'm sure that you'll find it and you don't need to upgrade anything on your laptop.