The Apache HTTP Server access logs are disabled by default. To enable them, do the following:
#CustomLog logs/access_log combined
Note that if you simply enable this directive, Apache will write the access logs to /Applications/MAMP/Library/logs/access_log , which is probably not what you want. It is better to store the access_log to /Applications/MAMP/logs/ , which is where the MySQL logs, PHP logs and Apache error logs are kept.
CustomLog /Applications/MAMP/logs/apache_access_log combined
$ /Applications/MAMP/bin/apache2/bin/apachectl restart
$ tail -f /Applications/MAMP/logs/apache_access_log
::1 - - [04/Jun/2010:10:32:20 -0700] "GET /favicon.ico HTTP/1.1" 200 1406 "-" "Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:188.8.131.52) Gecko/20100401 Firefox/3.6.3 GTB7.0"