Have you looked at blurb's offerings?
You can do a nice looking trade book for under $10 a copy. Sure, a gigantic heavy coffee table book is gonna run in the general area of $100 a copy, with essentially no upper bound if you just keep adding pages. If you've pre-sold enough volume, you can switch over to their offset service and go quite a bit cheaper per unit.
Basically there is a quality and a size for any price point you can dream up over about $2.00 a copy.
The point is not that blurb is great, the point is that there are a dizzying array of options. You can try for a relatively high volume cheap book. You probably COULD sell 1000 copies of a trade book at $10 a pop, looking to clear a couple bucks a book yourself (not including labor, ha!). You might be able to sell an edition of 25 or 40 high end books at $500 a pop. This is basically the Victorian model.
With print on demand and kickstarter, you could do both.
Back me at $500, get the coffee table book, the calendar, and the trade book, OR a folio of 10 8x10 prints, OR whatever.
At $25, you get the trade book.
At $50 you get the trade book and the calendar.
At $100 you get the trade book, the calendar, and an 8x10 print.
Etc..
As for personal experience, I have a flickr account with 653 followers, and I have verified that I can make that number go up more or less at will by spending time searching, commenting, and following people. The account is now largely fallow. However, over the approximately 1 year (I think) that was experimenting, active, and had a few hundred followers I got 2 or 3 queries about whether I would do a book. Those queries, I feel, represented a pretty accurate count of books I could sell immediately. So, I estimate roughly one sale for every 100 to 300 followers, let's say. On that account, with that content. Your mileage may vary.
So, I've printed a bunch of things at blurb at various price points. I've experimented with social networking. What I have not done is put the two together, for that I must rely on looking at funded kickstarters. They seem to have done essentially things I have done, more vigorously and at more length.
They probably had a bit of luck. It's not a sure thing, by any means, but it's a pretty well defined path, and you can operate it to minimize out of pocket costs.
I was shooting nudes, which, as I said, makes things a lot easier.
There's no reason the same ideas wouldn't apply to any genre, though. There's an audience for anything.