Nothing could be easier. Download db-xxx-src.tar.gz. Decompress the archive with an appropriate tool, for instance: tar ou WinZip.exe in Windows.

   db-1_0_1/
   db-1_0_1/.cvsignore
   db-1_0_1/about.c
   db-1_0_1/autogen.sh
   db-1_0_1/bitmaps/
   db-1_0_1/bitmaps/all-c.bmp
   db-1_0_1/bitmaps/all.bmp
   ...
   db-1_0_1/langs/
   db-1_0_1/langs/CVS/
   db-1_0_1/langs/CVS/Root
   db-1_0_1/langs/CVS/Repository
   db-1_0_1/langs/CVS/Entries
   db-1_0_1/langs/de.rcp
   db-1_0_1/langs/en.rcp
   db-1_0_1/langs/fr.rcp
   db-1_0_1/langs/it.rcp
   db-1_0_1/langs/ja.rcp
   db-1_0_1/langs/nl.rcp
   db-1_0_1/langs/no.rcp
   db-1_0_1/langs/pt.rcp
   db-1_0_1/langs/sample.rcp
   db-1_0_1/langs/sk-1250.rcp
   db-1_0_1/langs/sk-il2.rcp
   db-1_0_1/langs/sk.rcp
   db-1_0_1/langs/sv.rcp
   db-1_0_1/langs/es.rcp
   db-1_0_1/langs/ca.rcp
   ...