Mat Kirkland shares an effective little routine that will detect AutoCAD Civil 3D alignments in a given drawing file. You'll probably want to use this as part of a larger routine. This function requires one argument, and that is a reference to an ActiveX document which at the most basic level can be obtained with the function (vla-get-activedocument (vlax-get-acad-object)). If one or more alignments are found, this function returns a grouped pair, where the first element is an integer representing the number found, and the second element is a list of the Vla-Objects found.