Older article but I found this part interesting...
http://www.mywesttexas.com/top_stories/article_866f96aa-2c33-11e0-a0c4-001cc4c03286.html
There are certain basic responsibilities for law enforcement and the parents of missing children alike when a case is fresh, according to the National Center for Missing & Exploited Children, in which guidelines for each place a significant emphasis on the first 24 to 48 hours.
For law enforcement those steps include obtaining a detailed description of the child, searching a child's room as soon as possible and reviewing sex offender registries to determine whether individuals designated as sexual predators live or work nearby or might otherwise be associated with the child's disappearance.
Kampfer said that the Colorado City Police Department and others worked from a similar checklist as they were attempting to run down leads,
though law enforcement were initially frustrated at stories found to be "contradictory" from certain initial interviewees.