Can somebody flat me an area?

Hi,I started to create my first own little airport in Arizona, and so I tried to flat the area and to exclude all trees. To do this I used the programs I could find here in the forum (FSTFlatten...). But I just got error messages (e.g. in FST Flatten over 5 until the program started). So can someone please flat me the area and exclude all trees? Here are the facts:N32'59.42 W111'23.57N32'59.69 W111'17,87N32'55.45 W111'16.08N32'55.91 W111'22.591550 feetEmail: [email protected] you a lot :)