Hello,
I've released alflac, a library for adding support for FLAC (Free Lossless Audio Codec) files in Allegro. It's really a wrapper for the stream_decoder module in libFLAC (that code is included). I'd realy like it if it can be added to the list of libraries on the site.
FLAC files are a way to compress .wav files really well (generally goes to about half the original size). If you have over 100 KB of audio files, you'll probably save space by using alflac.dll.
To use it, add alflac_for_allegro() somewhere after allegro_init(), and then you can use load_sample("whatever.flac"). When you compile, you'll need to link to alflac (-lalflac) and #include <alflac.h>. Note, it'll take a moment longer to load (but not much longer).
You can also add .flac files as data in a datafile: if you give it the ID "FLAW", alflac will convert it to a SAMPLE when you call load_datafile. Again, you need alflac_for_allegro() after allegro_init().
There's also some streaming stuff for more advanced use.
Download alflac here (BSD license):
http://sourceforge.net/projects/alflac
(or http://compunach.co.nr/alflac )
Alflac only decodes the files (to keep the .dll small), so to make FLAC files from .wav files you'll need to download flac:
http://flac.sf.net