I'm looking to locate an ideal position by creating a cross over with the perfect slope angle and aspect so that the location is sheltered from prevailing winds. how do I get the information to do this?
It depends where is your study area.
But generally you will need a dem (digital elevation model) from which slope and aspect can be derived.
A common source is the aster dem. Widely available for download.
Do you have spatial analyst?
A good starting point for your search may be Digital Elevation Model (DEM) Discovery Portal | NCEI
also USGS SDTS format Digital Elevation Model data (DEM) With info about there downloads USGS SDTS format Digital Elevation Model data (DEM)
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