When using the above recommendation, my js function was still alerting null for the treeview. I changed 'find' to 'get' and I was able to retrieve the treeview object (the js function alerts '[object]'). When I append .findNodeByValue, I get a js error saying the method isn't supported by the object. The following is what I'm using to test it. Is there anything else I can try?
var node = $get('<%=RadTreeViewProject.ClientID%>').findNodeByValue(text);