To download the latest version of DOPAL, you can go to DOPAL's released files page on Sourceforge here.
DOPAL is packaged using distutils - there are binary installation files for some systems. If there is not an appropriate installation file, you can download the archive file - extract it and read the README file.
More information about installing distutils packages can be found here.
You can also download a zip file containing all the Epydoc generated API documentation for the module from here.