i race track.
another link to check out is
www.fixedgearfever.com. it's a great site with links to all the velodromes. it's run by a local racer here.
as others have suggested, go find your nearest velodrome and ask about beginner clinics, etc. more than likely your conversion won't be legal, unless the track is not very steep. i'm pretty sure all the ca tracks are steep ones though.
does anyone know if the l.a. one is open for local racing yet? when it first opened they were just doing nationals there, but not local stuff...