Hey Glyn,
Did you read as far as the part that says :
"Note: If the program does not appear in Add or Remove Programs, you might need to remove it using one of the automated tools listed below.
To attempt to remove this program and any similar programs that might be installed on your computer, you may download and run one of these free tools:
Microsoft -
Microsoft Windows AntiSpyware (Beta)
Third-Party Security Partner Tools -
Spybot Search & Destroy
Lavasoft Ad-aware "
These free downloads can then be run on your PC and should find and remove the IBIS program.
You can also do a "google" search on the Internet for "IBIS" - there's a lot of info there.