I apologize if this sounds a bit rude, but this is not some kind of corporate (or organized) service, and nobody's holding out on you.
Generally, any scans that are available (and in the public domain, and pre-1960) are already going to be here, and I'd guess that anybody reading here who has books that fit the bill are already planning to scan them. The scanners are doing (sometimes literally) backbreaking labor to produce the scans solely out of the goodness of their hearts, and are therefore not the sorts of people you want to try to micromanage. Nobody is sitting on scans, just waiting for them to be requested.
I don't want to single anybody out on this, but I do need to stress that pushing is probably more likely to delay the books, not speed them up. That probably goes especially for someone the community has never seen before and has not talked about anything else.
So, in short, relax a little. People know you're on the lookout, and short of buying and scanning the books yourself (always an option, and very welcome around here--the scanners you're waiting for are merely people who have done exactly that), that's about all you can do.