Not to jump the gun here, but I think a few of these trees might already be dead. Pines take quite a while to die, so if they are looking pretty bad and getting worse, they are probably dead already. You could get these trees in a mix of akadama, pumice and lava rock. This would provide a better growing environment as far as drainage. However, removing them from the container they are in might stress them further.
Personally, I don't think the nursery should have sold these to you, unless they were extremely reduced in price or free. If you are lookign to work with these. You will need to wait until they regain their health, which might be a couple of years. Then you might be able to start training them. If you do stick with these, you are looking at about 8-10 years before they become bonsai. Also, even then, they might not be nice specimens.
Rob