If you still have the hardware to play cassette( I am assuming it is a cassette), then just run a headphone-headphone cord from the stereo to your pc. Use Audacity to record your cassette. It'll take some fine tuning so you need some patience. Once you got everything recorded to your liking, you can use Windows Media Player to burn an audio cd of your music.
I know headphone-headphone cord isn't the proper term. It's a cord with an audio peg on each end usually used for pluggin something into an auxillary port on a stereo.
Oh and if you don't have a stereo, go borrow one. Almost everyone I know still has a stereo that plays cassettes.