HOw to create contours/bathymetry from XYZ point shapefile

[RachelS]

HI,
I have a shapefile that contains XYZ data for a lake. Can someone take me through the steps to create contours and then a raster of the area showing the increasing depth.
I'm confused whether to create DEM, ASCII or grid.
All the info for a contours seem to be creating them from DEM which I don't have.
I have spatial analyst and 3D analyst and ArcGIS 9.3.1.

Many thanks
Rachel

[DeepikaJain]

Hi

Please try the following link for the web help to resolve the issue:
http://webhelp.esri.com/arcgisdesktop/9.3/index.cfm?id=1243&pid=1237&topicname=Topo_To_Raster_(3D_An...)