Where can I learn to rip models? Specifically from the Metroid Prime games.

[Garamonde]

Well, for starters, AFAIK the Metroid games don't use a known format so they can't be converted with tools. Therefore they can probably only be gotten with printscreen rippers and that can be very difficult to achieve which is why it's not so much a matter of no one willing to help, but it could be a matter of actually being able to rip them properly with no issues.
For DS games it's definitely close to impossible to properly or even decently rip the models because there are almost no tools or converters besides printscreen rippers (and as mentioned, close to impossible or extremely difficult to get a good rip without any harmful issues this way) so that's why you practically never see DS model rips.
I hope you do find a converter for the models or get someone to code one though because as it stands now I don't see anyone going out of their way to rip from those games unfortunately.