LaunchDaemon for auto starting Apache Tomcat on Mac OS X. Make sure you set the 'user' and the 'JAVA_HOME' properly. To find out where JAVA_HOME is on your machine run '/usr/libexec/java_home -v 1.6' or '/usr/libexec/java_home -v 1.7'. Follow this guide to install Tomcat --> http://wolfpaulus.com/jounal/mac/tomcat7/

org.apache.tomcat.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
        <key>Disabled</key>
        <false/>
        <key>Label</key>
        <string>org.apache.tomcat</string>
	<key>ServiceDescription</key>
	<string>Tomcat Servlet/JSP Server</string>
	<key>UserName</key>
	<string>.....</string>
	<key>GroupName</key>
	<string>staff</string>
	<key>EnvironmentVariables</key>
	<dict>
		<key>CATALINA_HOME</key>
		<string>/Library/Tomcat</string>
		<key>JAVA_HOME</key>
		<string>/Library/Java/JavaVirtualMachines/jdk1.7.0_45.jdk/Contents/Home</string>
	</dict>
        <key>ProgramArguments</key>
        <array>
                <string>/Library/Tomcat/bin/catalina.sh</string>
                <string>run</string>
        </array>
        <key>RunAtLoad</key>
        <true/>
	<key>KeepAlive</key>
	<true/>
</dict>
</plist>