Having fscked about with this for quite a while, and seen how much hassle it is for audiophiles who care a lot more than I do, I suggest giving up while you're ahead. My approach when I finally got down to a small number of LPs that couldn't be found either in shops or online was to pay one of said audiophiles to rip the last 10 or so for me. Much cheaper overall than the time and hassle involved in ripping them all myself (I suspect the record companies are counting on this... and hoping we don't just download the illegally instead).

Actually, the best bit was tracking down and emailing a couple of the artists and in one case getting a CD directly with everything he had from the band he used to be in. Years later the album was released with 15 tracks instead of the 24 that I have :) The other group decided to put out a "when we were young" CD after all, since it's pretty cheap these days even with remastering costs. Both times I was happy to pay the artists for the CD.

Of great benefit there has been the recent Flying Nun retrospective collections and a couple of other compilation projects, because now I even have music videos from the olden days (New Zealand music from the 80s). Hopefully the more luddite record labels will eventually realise that this is a cheap source of profit too (remaster to CD, sell double CDs for $20... it's like printing money).