TypeConvert is the ArcGIS 9 extension allows you to convert one type feature class to another type feature class.
Typeconvert is free. Free registration include into this post.

For installation ArcGis 9.2 and Net 2.0 is required
Home page | Download | FAQ Download version for ArcGis 9.2 and Net 2.0
Download version for ArcGis 9.1 and Net 2.0
Download version for ArcGis 9.0 with SP3 or later.
Also we recommend to use module
KMLeras an extension for professional work with Google Earth.
Functionality:
Polygon <-> Polyline <-> PointsConvert one type feature class to another type feature class.
To ConvexHull and To envelopeConvert feature class into convex hull or envelope. In this case new polygon feature class containing only one feature (convex hull or envelope) will be created.
To centroidCommand allows you to create a new point feature class with all attributes from the center points (centroids) of the features in the current layer. A centroid of a feature is the spatial location of its envelope center. Additional fields 'Z','Zmin' and 'Zmax' are created if feature class with MZ geometries is converted.
To segmentsCommand allow you to convert polyline or polygon feature class to polyline feature class, consisting of lines segments of an initial feature class.
From graphicsCommand allows you to convert graphics elements of the active map into features. New created features are stored in corresponding feature classes, according to their geometry types. Names of new classes consists of a name, set by the user and a suffix, indicating geometry type (e.g. "classname_polyline"). Text associated with the graphics is stored into 'Text' field of the target feature class.
Remove duplicatesCommand allows you to remove duplicate features from the current layer. All 'cleaned' features are stored in output feature class. All 'removed' features are stored in additional output feature class with "_duplicate" suffix. Two features are compared by coordinates only without taking into account any difference in attributes.
StratificationCommand allows you to stratify current layer, classified by categories or quantities, to set of layers according the current legend. The layer must has symbology, based on single field. Names, aliases of the new feature classes are based on a attribute name, value of a class and a label of a class. All created feature classes keep attributes of source feature class. Styles of classes and categories are kept in new layers.
Divide segments. Add points to long segments of current feature class.
To *.blnCommand allows you to export feature class with 2-dimentional geometry (polyline, polygon) to blanking file (*.bln) for using this file in Golden Software Surfer.
To Google EarthCommand exports feature class to KML-file for using this file in Google Earth. If you have Google Earth installed, all you need is just click on the *.kml file you have created for a superb visualization of the results in 3D.
AboutOpens the window of the information on the current version of the program and registration.