Well, by accident I discovered a pretty cool trick.
I have found that you can extract Some/Majority of SFX through this neat little effect.
I don't know if it will work on bigger things like Mermaid Melody or Sailor Moon transformations, but it seemed to work well with my Tokyo Mew Mew Audio.
Sure there will be some BackGroundMusic when you extract it but when you lay it over new music you cannot hear it! =)
Ok, here are the directions exactly.
1. Open Audacity (The NEW BETA Version)
2.First, get a 2 channel stereo of your audio. MP3 works best or Original WAV audio from the DVD.
Import it in.
3. Go to Effect-Vocoder
4. Add an Echo Delay 0.2 Decay Factor 0.5
5. Remove and pick out what SFX you think will do best for your fandubs.
I hope this helps someone! I Know it helped me quite a bit!