Do you mean this http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//001700000032000000 tool? 'Add X Y Coordinates'?
or http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#//00170000006z000000 ' Make X Y Event Layer'?
The first one adds x and y coordinates to an already existing points feature class (not what you want).
The second one will create a temporary points layer based on a table, which may be what you want, although if you're starting from an Excel spreadsheet you might have to convert it to a .dbf or geodatabase table first, or at least check that the field headings are 'safe' for ArcGIS.
Usually if I'm plotting points based on XY data in a spreadsheet I'll use the 'Create Feature Class' -> 'From XY Table' right-click option in ArcCatalog, as this creates a permanent feature class rather than a temporary event layer. (I'm using 9.3 though, it might have changed in 10).
Hope that helps
Someone gave me an Excel spreadsheet with GPS coordinates on it of certain points in a field. the 'northing' points are in one column and the 'easting' points are in another.
I figure that there has to be a way to insert these points on an ArcMap 10 map and give them symbology. I was thinking that this way is the 'Add X Y data' tool under Data Management tool group. (am I right?)
If I am right, I have questions on the format and precedure for entering the data. this tool asks for an input. What does it want? A text document? The 2 excel columns?
thanks for any help!!