Or you can try dmesg, and see the boot-up messages. You should see some good info there.
hda: Maxtor 92048D8, 19531MB w/1024kB Cache, CHS=2489/255/63, UDMA
thats what I have, gives basic info.
more can be found in /proc/ide just look around and cat stuff.
and hdparm will can be used to benchmark your drive..
Hope it helps,
-Phil