Check out the folks at Tracer Technologies (www.tracertek.com).
They evolved from the Diamond Cut Audio, whose initial work was with
vertical Edison recordings.

I have a copy of their DCSix program, which works great.  I've
transferred a number of vinyl LPs to CD using it, eliminating clicks,
pops, and some hiss along the way.  Ironically, doing this made me
acutely aware of my need for a better turntable.  ;-)

Among other things, they recommend keeping the signal path from the
record to the computer as simple as possible, for example, use a flat
pre-amp, then apply the RIAA equalization to a copy of the WAV file.

Of course, they sell premier sound cards and flat pre-amps, as well 
as software.  Their web site, and their newsletters, tell the story.
Give them a try!

Steve McCollum

 [ Flat frequency response from pickup to WAV file is a good idea
 [ because it preserves the waveform of short impulse noise so the
 [ subsequent noise removal process will be better able to discern
 [ noise from valid music.  -- Robbie