Chinese historical books online

Apparently it is possible to buy hard to find items in Chinese historical bibliographies online. From Frog in a Well China blog:

"So after getting consumed in the twice weekly book market near 杜甫草堂 Du Fu’s Cottage soon after arriving in Chengdu earlier this year, I was pleasantly surprised that some random, non-linear meandering online brought me to a web resource that has been absolutely invaluable for discovering just what lies within those dusty piles. 孔夫子旧书网 Kongfz (http://www.kongfz.com/index.php) is a bit like Biblio with which many of you might be more familiar. The site claims to be: 全球最大的中文旧书网站 Its constantly growing database renders easily searchable the holdings of literally thousands of bookshops in all corners of the PRC, large and perhaps surprisingly minuscule. Indeed, what I found when I went looking for one of these ’shops’ in Chengdu was the owner and his brother having a quiet lunch in their sparsely furnished flat, while each room in the flat across the landing was overflowing with the books they had for sale. The booksellers themselves maintain their own online databases and many seem to add new books daily, as well as sell books daily, so there’s a bit of urgency sometimes to reserve what interests you the moment you see it as the next day it may already have been sold.

Most of the books on offer are out of print, published over the last two decades or so, (as print runs were generally quite small), but what’s available goes well beyond such more purely secondary sources. Many published collections of archival materials as well as 地方誌 both old and new and other collections of original materials are available for sometimes widely varying prices, as well as reprints of Qing or Republican era books. Among the items I’ve purchased was a 油印本 version of a book which original a certain library in Chengdu was only grudgingly willing to let me see, but certainly not photocopy or even photograph."