Restoring a Shared Service Provider can be a frustrating task. Especially when the feedback you get from STSADM doesn't help. For example, when the SSP has not been deleted before doing a NEW Restore, the Shared Search Service restore will stall at 90%. It will stay at 90% until you kill the process (CTRL+C).

Make sure that you delete ALL associated DBs. STSADM will ask you for a new name for each DB before it tries to restore them, so you could delete DBs as it asks if you aren't sure.

It is also recommended that you stop the SPSearch service. Here is the process for restoring a SSP...

Stop Search: (Delete the Search Index when asked)
stsadm -o spsearch -action stop

Delete all SSP DBs and Search DBs.  If you are not restoring ALL of you SSPs, then

Get Backup GUID Command:
stsadm -o backuphistory -directory

SSP Restore Command: (Restore all SSPs)
stsadm -o restore -directory -restoremethod new -backupid -newdatabaseserver

Reset IIS Command:
iisreset /noforce