In a recent blog post one of our IT Pro Evangelists shared two iSCSI target software solutions that offer trial editions of their software.
Free iSCSI Target Software
[MSFT-BE] Arlindo's Blog - IT Pro Evangelist : Free iSCSI Target Software
Several people asked me about iSCSI target software this week and where they might find a solution to test. I haven't worked with either of these so let me know about your experience.