A case of UTI conflict! I would say that 'org.perian.flac' is the incorrect UTI for FLAC files, because FLAC is not Perian's own format. I use 'org.xiph.flac' in my apps as the FLAC UTI. In any case, that doesn't help solve your problem.
The first thing I would try would be using the Finder to set a default application to open .flac files that uses a correct UTI for FLAC- Max or Play, for example.
If that doesn't work I would try duti which uses LaunchServices to set the default handler.
FLAC spotlight importer problems
Re: FLAC spotlight importer problems
Duti did the trick. Spotlight will search my FLACs now - many thanks! 

Re: FLAC spotlight importer problems
Hey guys,
After experiencing the same org.perian.flac problem, I fixed the problem very simply by rebuilding LaunchServices with Onyx after temporarily uninstalling Perian. Since I am on a 64 bit snow leopard machine, the plugin still does not work. I tried to recompile it for 64 bit using the 1.0 source but got compile errors. Could you give this a look, I'm sure a real programmer can take care of this quickly. Or at least upload the 1.1 working source.
After experiencing the same org.perian.flac problem, I fixed the problem very simply by rebuilding LaunchServices with Onyx after temporarily uninstalling Perian. Since I am on a 64 bit snow leopard machine, the plugin still does not work. I tried to recompile it for 64 bit using the 1.0 source but got compile errors. Could you give this a look, I'm sure a real programmer can take care of this quickly. Or at least upload the 1.1 working source.