This assumes you have already installed IBM Installation Manager.
The imcl (Installation Manager command line tool) command with the listAvailablePackages option can be used get the ID of the packages in a repository. In this example, the imcl command is located at /opt/IBM/InstallationManager/eclipse/tools/imcl but you may have the imcl command located at some other directory.
~]# /opt/IBM/InstallationManager/eclipse/tools/imcl listAvailablePackages -repositories http://www.ibm.com/software/repositorymanager/com.ibm.websphere.BASE.v90 -prompt com.ibm.websphere.BASE.v90_18.104.22.16871205_1311 com.ibm.websphere.ILAN.v90_22.214.171.12471205_1311 com.ibm.websphere.ND.v90_126.96.36.19971205_1311 com.ibm.websphere.NDDMZ.v90_188.8.131.5271205_1311
You can then use the viewLicense option followed by the ID to display the license for the package.
/opt/IBM/InstallationManager/eclipse/tools/imcl viewLicense com.ibm.websphere.BASE.v90_184.108.40.20671205_1311 -repositories http://www.ibm.com/software/repositorymanager/com.ibm.websphere.BASE.v90 -prompt
Viewing the license and understanding the license are two seperate things. This IBM article explains how to understand the license.