Even if old or new...they have em.
Linkies for examples:
All easily found by searching company web sites.
Western Digital
http://wdc.custhelp.com/cgi-bin/wdc....cGFnZT0x&p_li=
Seagate
One with picture (see section 3.3 Drive Mounting for picture):
http://www.seagate.com/support/disc/...omentus_pm.pdf
IBM (now Hitachi owned):
http://www.hgst.com/hdd/support/06613/06613mec.htm
Couldn't find anything with a simple search on Maxtor's site....but considaring how HDD's work...I'm sure if you call em, they will tell you where their vents are.
Moral of the story: DON'T SUBMERGE YOUR HDD!