It's possible to change the default location of where MSSQL stores its databases from inside MSSQL itself.
1. Open Enterprise Manager.
2. Expand the tree to find the server that you want to change the default location of databases for.
3. Right click on the server name and select properties.
4. Select the database settings tab.
5. At the bottom of this page you can set the default data and log directories that the database files will be created under.
6. You will probabyl need to restart SQL server for the changes to take efect.
HTH
Roland