External Soundcard - Help

[lfutten at readysoft.es]

Yeaps, I know this is kinda stupid, but I've purchased a portable 
puter, second hand, but it has no soundcard nor midi interface, nor 
anything but a floppy and a 540Mb HD.
Well, as PCMCIA seems a bit too expensive, I would like to know 
what you all recommend me to do.. How can I build a n external 
soundcard that can be powered via a 5v cable from the ps2 port?
Well, the portable has COM1, COM2, LPT1, PS2 mouse and PS2 keyboard 
connectors. COM1 and COM2 are interchangeable, that means, that you 
can't use it at the same time.
Is it possible to buy a soundcard, connect the part that goes to the 
slot, put it in a box, and run? If so, what are each end of the bus 
connector, and how / where can I sold it to  a LPT plug?
Is it possible?

Thanks in advance!

Luz Futten.
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