In Comparison Chart of Spotlight on Oracle Editions under Features there is one called "Alert Log Reader"
( information in the Help menu is missing part on how to get to the Alert Log option)
Help menu of Spotlight will be edited in a future build.
The Alarm log would be from the right click on the left (on the connection), but the Alert Log would be the last tab on the right (assuming that the Xpert key is used otherwise it will not show). It means you would click on Configuration & Memory Drilldown icon and then the Alert Log tab will be on the right had side.
Please note that this tab will not show if the license is not an Oracle Xpert license (you can verify that from Help, About Spotlight , Modules tab.