Hi,
What FW is it?
You can see logs in ASDM (GUI interface). Access the ASA through the GUI interface (ASDM).
Once you log in to the ASDM, go to
Configuration > firwall > access rules
Right Click on the rule that you had created and choose show log.
You will be able to see the ip addresses hitting it. The real time application of the rule.
For logging.
Install a syslog server and configure the FWs syslog server settings to point to that server.
Hope this helps. Let me know if you need more help.