There are a large number of bibles that can be found that FreeWorship can import. I have started putting together a list of some of them below. Once you have downloaded a bible make sure it is extracted from any zip files and has the extension .xml before trying to import it to FreeWorship. To import it to FreeWorship go to Database > Import > Bible.
The OpenSong Bibles are often in a .zip folder and sometimes the file inside has a different extension other than .xml. Can you check that the bible has been extracted from the zip and renamed so that it has a .xml extension if needed then try importing it to FreeWorship again. Let me know if there are any problems.