Hiya,
I was actually fortunate enough to find the LD-ROM module on e-bay
about a month ago. I payed around $200 for it. I've been actively
looking on e-bay for one, for about a year, and that was the first
one I've seen by itself. I have seen 4 or 5 sold with the LaserActive
player and Sega module for around $800. If you are looking for the
games, they have all the U.S. titles on sale for $5 at www.lvd.com
except for Blue Chicago Blues which I am still looking for.
Good luck,
Shane