This is the list of what I did to compile and install xsane-win32.
Some parts may not be exact because I wrote them down from my mind.


I) Needed installation of cygwin:

    I.1) go to http://cygwin.com
    I.2) click the install cygwin button
    I.3) follow the instructions (I installed all packages
         but not all packages are necessary)
         - install to c:\cygwin
         - use preselected options
    I.4) mkdir c:/sane

    I.5) cp /bin/cygwin1.dll c:/sane
    I.6) cp /bin/cygjpeg*.dll c:/sane
    I.7) cp /bin/cygpng*.dll c:/sane
    I.8) cp /bin/cygtiff*.dll c:/sane
    I.9) cp /bin/cygz.dll c:/sane
    I.a) cp /bin/cygintl.dll c:/sane



II) Needed gtk+ and glib:

   II.1) get glib-dev-*.zip and gtk+-dev-*.zip and iconv-dev*.zip
         from http://user.sgic.fi/~tml/gimp/win32/

   II.2) start cygwin bash shell
   II.3) mkdir /src

   II.4) unpack gtk+, glib and iconv to c:\cygwin

   II.5) cd /src/glib
   II.6) cp *.h /usr/include
   II.7) cp libglib*.a /usr/lib
   II.8) cp glib-*.dll c:/sane

   II.9) cd /src/gtk+/gdk
   II.a) mkdir /usr/include/gdk
   II.b) cp *.h /usr/include/gdk
   II.c) cp libgdk-*.a /usr/lib
   II.d) cp gdk-*.dll c:/sane

   II.e) cd /src/gtk+/gtk
   II.f) mkdir /usr/include/gtk
   II.g) cp *.h /usr/include/gtk
   II.h) cp libgtk-*.a /usr/lib
   II.i) cp gtk-*.dll c:/sane

   II.j) cd /src/libiconv*/src
   II.k) cp iconv*.dll c:/sane


IIb) If GIMP-Plugin shall be compiled (otherwise skip this section):

  IIb.1) get gimp-dev-*.zip
         from http://user.sgic.fi/~tml/gimp/win32/

  IIb.2) unpack gimp-dev to c:\cygwin
  IIb.3) cd /src/gimp/libgimp
  IIb.4) mkdir /usr/include/libgimp
  IIb.5) cp *.h /usr/include/libgimp
  IIb.6) cp gimp-*.dll c:/sane
  IIb.7) cp libgimp-*.a /usr/lib


III) Needed sane-parts:

  III.1) copy sane-source-package to /src
  III.2) cd /src
  III.3) tar xvzf sane-*.tar.gz
  III.4) cd /src/sane-*
  III.5) edit backend/net.c and change sanei_backend.h to sanei_backend_win32.h
  III.6) cp src/sane-*/include/sane/sanei_backend.h to include/sane/sanei_backend_win32.h
  III.7) remove all lines containing "ENTRY" from sane/include/sanei_backend_win32.h
  III.8) call ./configure --prefix=/cygdrive/c/sane
         (do not use c:/sane because ":" is used as path separator)
  III.9) edit backend/Makefile
          - remove all backends but net from PRELOADABLE_BACKENDS
          - remove dll from ALL_BACKENDS
          - add net to DLL_PRELOAD
          - remove dll.lo dll-s.lo from line beginning with "libsane.la:"
  III.a) Remove lines with isfdtype and vsyslog from sanei/sanei_init_debug.c
  III.b) compile sane (in directory sane-1.0.*) (call make)
           this should create a file backend/.libs/libsane.a and frontend/scanimage.exe
  III.c) mkdir /usr/include/sane
  III.d) cp include/sane/sane.h /usr/include/sane
  III.e) cp include/sane/saneopts.h /usr/include/sane
  III.f) cp backend/.libs/libsane.a /usr/lib
  III.g) cp frontend/scanimage.exe /sane



IV) compiling xsane:

   IV.1) copy xsane-source-package to /src
   IV.2) cd /src
   IV.3) tar xvzf xsane-*.tar.gz
   IV.4) cd /xsane-*
   IV.5) edit configure and remove "exit" after "ERROR: SANE" and "ERROR: GTK"
   IV.6) copy src/Makefile.in.WIN32 to src/Makefile.in
   IV.7) call ./configure --prefix="c:'\\\\'sane"
              ignore errors about missing gtk, gimp and sane
   IV.8) In src/Makefile do:
         - check GTK-DLL names, GDK-DLL names in GTK_LIBS:
           GTK_LIBS = -lgtk-1.3 -lgdk-1.3
           and name of gimp-library:
           GIMP_LIBS = -lgimp-1.2 -lglib-1.3
         - When you want to compile xsane without gimp support:
           comment out GIMP_LIBS ... with a "#"
         - When you want to compile xsane with debug output,
           remove "-mwindows" from the CC=... line
           (this creates a Dosbox when xsane is started,
           XSANE_DEBUG=128 and SANE_DEBUG_NET=128 enables
           debug messages)
   IV.9) compile xsane (in directory xsane-0.*/) (call make)
   IV.a) make install




V)  set up correct environment

    V.1) mkdir c:/sane/etc
    V.2) mkdir c:/sane/etc/sane.d
    V.3) vi c:/sane/etc/sane.d/net.conf
         and enter a list of NetBEUI names or of IP-addresses
         of machines you want to connect to. On some Windows
         system IP-addresses are not accepted; if you experience
         any problems try the NetBUI names.

         example for net.conf:
          myhost1
          myhost2.mydomain.com
          192.168.0.1
          192.169.1.73
    V.4) mkdir c:/sane/home
    V.5) mkdir c:/sane/home/xsane