No problem to do this at all. Here's a guide:
1. Get yourself a decent mic. Don't get the cheapest one you can find but something reputable from a company like Plantronics or Logitech
2. Download a copy of audiograbber from here:
http://www.audiograbber.com-us.net/ This is a great application that I once paid for, but luckily for you has now become freeware. Get the LAME MP3 DLL while you're there and be sure to put it in your audiograbber directory after installation.
3. There is a "Line In Sampling" menu option that will record from your mic plugged into your soundcard. Before you choose that be sure ot put a tick in the MPŁ box and change the settings to the bit-rate you want
Hey presto MP3 files of your voice ready to transfer.