In the Lightwork project (http://lightwork.massey.ac.nz) and (http://moodle.org/mod/data/view.php?d=13&rid=2743 ), we needed to create test data which we tear down and recreate for each of our bi weekly releases. Since much of the data had to be created and modified by non technical users we have used an Excel spreadsheet to do it. A simple macro converts the spreadsheet data into SQL which drops the tables and recreates them.
The spreadsheet can be freely downloaded from our site and can be used as is or as a template for different test data. If test student submissions are required, the test mdl_assignment_submissions data can be used in conjunction with a zip file containing test submission files.
The spreadsheet is at http://tur-applrnd4.massey.ac.nz:3000/repositories/changes/fat/trunk/lightwork/nz.ac.massey.lightwork/db/sql/mdl_test_data.xlsm
The test files can be found at http://tur-applrnd4.massey.ac.nz:3000/repositories/changes/fat/trunk/lightwork/nz.ac.massey.lightwork/db/sql/TestDataOct2009.zip