Everyone who was old enough to be listening to music pre-CD has a collection of grooved vinyl records and magnetized tape cassettes stashed somewhere. Those records are not only great for the cover art; some of them have music that still sounds great. Now there has been a concerted effort to develop the hardware and software to allow you to convert that music from its current analog form to digital, and reorganize it on a CD or an MP3 player.
First, of course, you're going to need a turntable and/or a cassette player. You'll be using a computer to convert your old music to digital format, so a cable that connects the turntable or cassette player to the PC (or Mac) is also in order. Apparently cables that have the old audio jacks at one end and a UBS connector at the other are relatively common and can be found in electronic emporiums such as Radio Shack.
Your computer will need to have a sound card - sound cards have been standard issue for PCs for some time. You may also need to incorporate an amplifier of some sort into the mix, as the turntable or the cassette player alone may not generate enough sound. That shouldn't be too difficult however - the amplifier that drives your current sound system still has "audio in" and "audio out" jacks, no matter when it was built.
The final element in the process is the appropriate software. While you can purchase software for this purpose, there is also freeware available: one example is an open source recording and editing program called Audacity, found at http://audacity.sourceforge.net/. Adobe has a program called Encore that is available for a 30 day free trial, and for Mac users there's GarageBand, which is part of a Mac software package that is sold through retail outlets.
That's the package. Once you're in upload mode with your old school hardware, you'll have to stop after each song in order to make it a discrete recording. There's a fair amount of oversight to all this, especially if you've got a lot of records. It's one tune at a time, unless you want to upload the entire album as a single MP3 file. So the sentiment that's attached to those old tunes is going to come into play, as this can turn into a labor of love.
There's a streamlining tool on the market from Audio Technica which is a turntable with all the right cabling, amplification and software. A similar product can be found at www.firebox.com which is called a USB Turntable. The cost on these conversion spinners is $100 - $130 dollars.
There are also some online services available that will make the conversion for you - but most of them appear to be pricey. One service, http://avconvert.com/audio/price_list_cassette.html, will not only convert your LP or cassette tape but will remove any audio flaws and reproduce the cover art as well. You send them the recording and they do the rest - but the prices are twenty dollars or more, depending on the medium and the level of service you desire.