Pokemon Battle Revolution Question

[Failtastic]

Okay, so I was looking through my old PBR guide. And, basically, it has everything on how to get anything, but I'm still curious about one thing.
How are you supposed to get the alternate outfits? I already have all 6 outfits on one file, but I read somewhere that if you have the standard one, you can't get the alternate one. I still wasn't sure, so I made a second file. I already have both files beaten, and I've still yet to get any outfits on the second.
Input appreciated. Thanks in advance. :)

[Neon_Espeon]

Describe "Alternate Outfits". Do you mean the ones that some of the Colliseum Masters(or whatever they're called, I haven't the game In who knows how long...)wear(most notably the ones who wear the Pokémon-like outfits) that you can get after you beat them, or just the normal buy-able clothes? If It's the first thing, I'm pretty sure you should have them all given you beaten the Pokémon outfit wearing Colliseum person. If It's the second, I'm not really sure. Again, If you beat the entire game and whatnot all the clothing and accessories should be available to buy. But I could be wrong, I haven't played the game In months and I forgot quite a number of things about It. =p But either way, I hope that helped In some way.

[Failtastic]

Well, it's basically the first one, but with alternate (shiny) colors.
The guide I bought says it's in the game, but it's pretty much near to impossible to get them. I was wondering if anyone knew if something else was involved other than just going through the coliseum until the Coliseum Master decided to pick out a shiny outfit. Other than that, that's basically all I needed. P:

[Pokemon Trainer Sarah]

I think you just have to be lucky enough to encounter the shiny-form when you battle them. As far as I know there are no extra tricks or anything, just luck.