After a bit of fiddling Apache Solr search is now installed and functioning.
Click here to use the new search. Several facets are available to quickly filter to the content you want.
A quick note about Apache Solr, if you had this module installed on Drupal 6 and upgrade to Drupal 7 you may need to uninstall (not just disable and delete the module files) the modules before the installation will work again. This appears to be due to some internally stored Drupal variables that were stored outside the module files.