1. Play tape in a good boombox or stereo
2. Connect headphones output to a PC sound card input
3. Record tape play as a WAV file in the PC
4. Burn resulting files to CD using CD software and Cd burner
Just about any online firm or computer store will have cables, CD burners, software, etc.
Remember though- some cd-r's are proving to have an even shorter shelf life than tapes, so by going the computer route, you can keep a digital copy on your hard drive(s) and of course make cds for listening / selling / archiving.