This past fall I started a Mac 512K blog. In it I document my discoveries and adventures with the 512K Fat Mac, including software, hardware, repair, peripherals, programming, and lore. The sources of information I draw on are primary-source documents (typically Apple), contemporary magazines, and Usenet posts.
Some of my recent articles covered the origins of HFS, the Hard Disk 20, repairing the 400K floppy drives, and making an RS232 link from an Intel Mac mini to transfer files. I have at least a dozen more articles planned, and we're going to go a lot further in depth and take the 512K Macintosh to its limits!
See the link below in my signature.