In addition to reading the page on SDN regarding osteopathic medicine, you can check out
<a href="http://www.aacom.org" target="_blank">AACOM</a>
and
<a href="http://www.aoa-net.org" target="_blank">AOA</a>
for general information on the 19 DO schools. There is also a lot of valuable information you can gain regarding DO schools from reading some of the message threads here on the SDN forums as well.
Hope this helps.