Here are a few options for building a DIY shockmount to be mounted on a boom:
An old thread discussing it here on indietalk: http://www.indietalk.com/showthread.php?t=8863
And a few other links from an online magazine site:
http://www.microfilmmaker.com/tipstr.../diy1shk1.html
http://www.microfilmmaker.com/tipstr.../diy2shk1.html
http://www.microfilmmaker.com/tipstr.../shock3_1.html
An old thread discussing it here on indietalk: http://www.indietalk.com/showthread.php?t=8863
And a few other links from an online magazine site:
http://www.microfilmmaker.com/tipstr.../diy1shk1.html
http://www.microfilmmaker.com/tipstr.../diy2shk1.html
http://www.microfilmmaker.com/tipstr.../shock3_1.html