The old SSModules web site, containing free downloadable library material for SwordSearcher, as been merged with the new SwordSearcher Forums. See the new module repository here.
There are plenty of extra books you can download and add to SwordSearcher. Plus, you can vote for your favorite modules (including ones included with SwordSearcher). SwordSearcher users who have created books can even upload their modules to share.
All you need to know about downloading SwordSearcher modules can be found here.
Even if you have used SSModules in the past, you’ll want to come take a look, as new modules not before available have been added. For example, earlier today the following free downloads were added: