Adding Dutch books is not all that easy. Proxis makes a poor provider because it doesn't have that many books on sale.

I see two great alternatives, but I don't know if it is possible to integrate those into Alexandria.
First: nl.bol.com (very wide range of Dutch books)
Second: http://zoeken.bibliotheek.be/ (this is the central catalogue of all Flemish libraries - a very very wide range
of Dutch books and books in German, French, English, Spanish, Arabic,...)

Date: 2009-08-04 11:42
Sender: Cathal Mc Ginley

The actual library code is under /usr/lib/ruby/1.8/alexandria
or /usr/lib/ruby/site_ruby/1.8/alexandria - depending on your
system. But if you're going to look at the code, you should check
out the development version.

This is a little out of date by now, but you can get a quick
introduction here:
http://www.gnostai.org/journal/2007/12/28/getting-started-with-al
exandria-development/

Date: 2009-08-04 10:48
Sender: Daniel de Wit

Hi Cathal,

Thanks for your quick reply.
I would be very thankfull with some documentation, then I can
finally make entries for the dozens of Dutch books I have. :)
I did some snooping around in //usr/bin/alexandria , but that´s
not where I should be right?

Date: 2009-08-04 02:59
Sender: Cathal Mc Ginley

Sorry, no progress on this yet. (And unfortunately, the old alexandria
wiki was lost). I'll try to write some documentation on how to
write your own providers (it'll require a small amount of ruby
programming, but can probably be managed by copying existing
web-based providers).

Date: 2009-08-03 14:52
Sender: Daniel de Wit

any progress on this, I´d love to see this feature too
Is there a way to do it manually?

Date: 2008-02-22 21:07
Sender: Cathal Mc Ginley

This has been added to the list of Suggested Providers on the
Alexandria wiki http://wiki.alexandria-projects.org/wiki/BookProv
iders

Date: 2007-09-25 18:42
Sender: Lennart Karssen

This is also mentioned (although with less suggestions) in Feature
Request #1619.