Just to chime in about Overclocked Remix, I also agree it could be a great source and honestly if more gymnasts were competing to video game music that would be amazing.
But specifically I thought I'd just recommend some video games that would be conducive to floor in general just due to their thematic points since you can search by games.
Final Fantasy: This series has a mix of music ranging from fast paced techno type to symphonic dramatic pieces, to just peaceful ones. Any of the games may produce that especially with the remixing done, but just as a starting point Final Fantasy 7, Final Fantasy 8, Final Fantasy 9, Final Fantasy 10 (or X) and Final Fantasy 10-2 (X-2) will provide a starting point. Final Fantasy 7 and 8 have more danceish songs including "Man With the Machine Gun" from FF8 which is crying out for a floor routine to be performed to it. Final Fantasy 9 is more orchestral. Final Fantasy is more orchestral, but also has a piece I believe called Blitzball which is very conducive to fast paced. Final Fantasy X-2 actually has soundtracks with shorter pieces closer to the actual length of routines and many have different personalities.
Super Mario Brothers: The original theme done on a 1985 system would not be suggested, but thanks to all the remixes, you can find it in nearly every genre of music. Though some of the pieces may be too silly to get the right mood going, there are also potentially very good pieces out there.
Legend of Zelda: I'm not as familiar with the later games, but the original game has a strong orchestral piece which flows to allow both tumbling passes and the dance elements.
Pokemon: Pokemon has a bunch of light orchestrals theme which could fit as well.
Mega Man: This is also a long series of games, but the composers behind the games tended to explore a variety of musical themes throughout and the remixers picked up on that. I tend to listen to a lot of this music and also tend to see paralells between many of the pieces being used now. You can pretty much find any sort of piece (outside of Orchestral flourish) in there.
Also if you can find the soundtracks on ITunes (Final Fantasy has a bunch on there) and most are instrumental. Vocals are rare in background music.