Thanks for the help and suggestions for getting disks on my Model III. I took advantage of Ira Goldklang's TRS-80.com site - and had disks mailed to me pretty quickly.
So now my problem seems to be the disk drives themselves. Between two Model III's I have 5 drives. One of the Model IIIs won't boot at all, the other seems to work but the "1" drive won't read anything. This working one came with a spare drive mechanism, hence I have 5 drives. None of the drives seems to work as Drive 1 in this machine.
Is there anyone in the Philadelphia area who has any experience with TRS-80s who might be able to lend a hand - or at least an ear? My goal is to make one good machine out of the two - and trash, sell, or giveaway the other.