Recently people have been asking me "where do you come up with your posts?" I don't think it's egotistical to admit that I think my posts are interesting. Of course they interest me! Anyone else who is interested enough to read or ask seems to find some of them interesting too. I was thinking about doing an "Anatomy of an On the Main Line post," and I'll do that sometime. But for now, I'll reveal some of my secrets, which should not be such a secret. First, there are generally two kinds of OtML posts. One is an analysis of a topic, be it some kind of biblical question concerning language or interpretation, or a historical question. The other is of the "here is a cool picture/ paragraph/ quote/ article/ essay/ antiquarian something-or-other." There used to be a third kind, a rant about something (generally Jewishly) political, or cultural, but I've gotten most of that out of my system! Here I will concern myself with the second type of post.
The answer is that I read a lot. Point a leads to point b, and that leads to point z, and sometimes it leads to point zxwr3$35. You never know. I don't have an amazing collection of seforim, books and periodicals, but I believe what I do own is judiciously chosen to interest me. I find material and leads there. I also go to libraries when I can, sometimes in search of something specific, sometimes not. But I usually come away with something of interest to explore further.
But then there are the riches and resources that are online, some free and some available via subscription.
Google Book Search is free, and it gets better every month (despite some real flaws). Not only is it a good resource, but if you play around with it you can even crack some of it's limitations. Their new agreement will only make it better.
Sometimes books which are unavailable there can be read (at least the parts I want) on amazon.com or bn.com. You never know, always check.
There are other digitization projects to check out, like the one on archive.org. The University of Michigan's Mirlyn library catalog was and is a good resource, as it incorporates all of the books Google has scanned from them but not placed online (provided there is no copyright issue).
Recently many libraries joined with U Mich and formed the Hathi Trust, which is like Mirlyn, only includes many more libraries. It will work as a backup of Google Books, and at the moment includes many things which Google did not yet put online.
There are free collections of digital material on many university web sites, such as this:
Many Jewish universities and libraries have valuable material.
There is the JNUL which has these:
TAU which has
JTSA's digital site is small, but really good
There is this
Then there are paid archives, which one can access through university subscription if one has such access, which one, of course, does.
There is JStor, there are databases by Proquest, Gale and Chadwyck-Healy.
There is the amazing, amazing hebrewbooks.org. There is still the very valuable seforimonline.com. There is Otzar Ha-chochma, the Bar Ilan Responsa Project, Daat, and there are great friends who I send things to and who send things to me. Of course, there are also the most valuable comments, emails I receive and posts by other bloggers to stimulate and inform me.
I can go on, and maybe later I will. But in short, there are TONS of material available for my posts, or any sort of posts. If my passion was the history of invention I could probably run a fascinating blog about that, at least one that fascinated me.
Ishim U-shitos figured it out.