I am having a similar problem with the installer like others. In my case it is with Dell equipment instead of IBM.
The equipment I am using is Dell R5400 and Optiplex 755. The Optiplex 755 has a OpenSolaris 2009.06 currently running on it.
First installation was attempted on the Dell R5400;
The Dell R5400 is bare metal new disks that has never had a OS installed.
I have downloaded both the Solaris 11 Express LiveCD and the text version installation .iso's.
Both installations fail the same way. I used the LiveCD boot to run format to label the disk's
The installer boots from CD OK but when going out to find disks it cannot find any no error messages just keeps on twirling the indicator.
When I exit the install and drop back to single user and run format I can see the drives and partitions. Booting up the Solaris Express 11 LiveCD I can see the drives with format and gpart and the installer still fails the same. I left the installer twirling the activity indicator for twenty minutes before giving up.
Boot the install disk, installer could not find any disks. From single user mode format finds the disk and reads the partion info.
I'm also having this problem on a system that has an ASUS A8N5X motherboard and a single SATA drive attached. It behaves just as you describe. This is disapointing as I have had no problems running Solaris 10 and OpenSolaris on this machine in the past.
UPDATE: After posting this, I tried again, and let it spin for about 10 minutes and it finally found the disk and allowed to continue installation normally. I guess it just takes a while! :\