That post from relicnews.com was pretty out of date, I've found some workarounds.
And yeah, Right Hemisphere bought the company that made 3D Explorer, turned it from shareware to trialware and upped the price to more than 300 bucks. Bastages.
Anyway, here we go:
You can download the tempest installer here:
http://www.turbosquid.com/gmax
Ignore it's rather long install instructions, you don't need most of it (including the Quake III Arena install it says it requires), just run the installer and it should put a bunch of stuff into gmax/gamepacks/Tempest.
Go into gmax/gamepacks/Tempest/plugins and copy md3exp.dle into the gmax/plugins directory, you can now export .MD3 files (the Quake III format).
Now you can search google for "md3 to 3ds" and find one of many tools that does it. I'm looking at using MilkShape 3D (
http://www.swissquake.ch/chumbalum-soft/ms3d/index.html) which only has a $25 registration fee and appears to support a LOT of formats. I haven't really tested it fully though, so I can't recommend it wholeheartedly.
If anything else comes up, I'll let you know.