Lets get a few things straight:
You WON"T be able to hook up your PC directly to your XL for data (SCSI, USB).
The XL doesn't have a function to mix down a finished beat inside the machine and save it as an audio file.
so:
The only way you are going to get your finished beat into your PC is to record it to the PC through an Audio interface/card or record it to a hardware recording device of some sort that you can transfer to your PC.
Do a search for what cards people are using to get their beats into the PC.
If you have the eight outs card on your XL you might want to look for a card that has 8 ins. There are a lot of topics discussing this pro and con.
The main connections you need are audio cables from your XL to a recording device, either a track recorder as you call it or your PC fitted with a sound card. Once you've got it in the PC use whatever to tidy it up and burn to CD.
It doesn't sound like you have any MIDI devices yet so ignore that for now and work on your beats.
Best suggestion is to research whats out there by reading all of this forum and others, make beats ,figure out what you can afford, make beats, read some more, make beats, ask some informed questions, make beats, buy it, etc.
Slick
P.S.
How are you saving your beats? ZIP, floppy, CF cards?