Another great community developed tool. This one takes some of the complexity about learning the CAML syntax for MOSS 2007.  The Stramit Caml Viewer 2007 allows you to connect to a MOSS site and reverse engineer the CAML from lists, etc.

http://www.sharepointblogs.com/gally/archive/2006/09/19/12432.aspx

http://www.codeplex.com/Project/FileDownload.aspx?ProjectName=SPCamlViewer&DownloadId=2350