Jenkins provide 'Email-ext' plugin, which allows to configure every aspect of email notifications.
One of my requirement is to send in mail the build package URL, which is already getting displayed in console output.
I found a token
${BUILD_LOG_REGEX, regex, linesBefore, linesAfter, maxMatches, showTruncatedLines, substText, escapeHtml, matchedLineHtmlStyle} - Displays lines from the build log that match the regular expression.
Here is example usage of it
${BUILD_LOG_REGEX, regex="^Build package URL:", showTruncatedLines=false}
This will extract the line starting with "Build package URL:" from the build log and send it through mail.