Use my laptop to record live music?

[rbjammin]

The laptop I recently purchased was going to be used primarily for work (cad and engineering software) and games, but now I'm wondering if it could be used for recording music as well. Here are some of the specs:

Pentium 4, 1.6 Ghz processor
512 M, DDR Ram
40 G HD (24 G available)
16x cd-r drive
Crystal WDM audio

(2) USB 2.0 ports
(2) PCMCIA adapters (Texas Instruments)

IEEE 1394 Bus host controller (whatever that is...)
IDE ATA/ATAPI controllers (I have no idea what this is either!)

Microphone line in
Line in / audio in

The big question would seem to be, how could I use this machine to record music? The music will primarily be band demos and my own stuff.

It seems I would need software (n-tracks seems to be a decent place to start), but how does one get from live audio to computer? What other gear do I need? What's the signal path? How does this all hookup?

Thanks in advance for any help or suggestions!