So now that Python has been proven as a great tool, who do you begin.  Sure you can start with www.python.org but the is so much information is on the site you are not sure where to start.  Well, there is a endless source for finding code samples.  Search the ArcGIS Help Library to find the tool you would like to use.  Then scroll to near the bottom and there is a code sample to use in the Python Window or as a stand-alone script for that particular tool.

Another  method that saves a lot of time is to use ModelBuilder and create a model for the desired process.  Once you get the model working then export the model as a script (Model > Export > Script).  The output of this export provides a great starting point for expanding on the python code to get the task accomplished.

Here is a quick example from the Buffer tool help document:

Python Widnow Script
import arcpy
arcpy.env.workspace = "C:/data"
arcpy.Buffer_analysis("roads", "C:/output/majorrdsBuffered" "100 Feet", "FULL", "ROUND", "LIST", "Distance")

Stand-alone Script
# Name: Buffer.py
# Description: Find areas of suitable vegetation which exclude areas heavily impacted by major roads
# Author: ESRI

# import system modules
import arcpy
from arcpy import env

# Set environment settings
env.workspace = “C:/data/Habitat_Analysis.gdb”

# Select suitable vegetation patches from all vegetation
veg = “vegtype”
suitableVeg = “C:/output/Output.gdb/suitable_vegetation”
whereClause = “HABITAT = 1″
arcpy.Select_analysis(veg, suitableVeg, whereClause)

# Buffer areas of impact around major roads
roads = “majorrds”
roadsBuffer = “C:/output/Output.gdb/buffer_output”
distanceField = “Distance”
sideType = “FULL”
endType = “ROUND”
dissolveType = “LIST”
dissolveField = “Distance”
arcpy.Buffer_analysis(roads, roadsBuffer, distanceField, sideType, endType, dissolveType, dissolveField)

# Erase areas of impact around major roads from the suitable vegetation patches
eraseOutput = “C:/output/Output.gdb/suitable_vegetation_minus_roads”
xyTol = “1 Meters”
arcpy.Erase_analysis(suitableVeg, roadsBuffer, eraseOutput, xyTol)

To perform a single distance buffer:

1. Open the Buffer Tool – ArcToolbox >Proximity >Buffer

2. Fill Inputs

• Input Features (Points, Polylines, Polygons)
• Output Feature Class
• Linear Unit (Distance of Buffer) This can also come from a attribute field value.

The remaining entries are optional.

The new output layer from the buffer will be added to the map (circles around red dots).

To perform a multiple distance buffer:

1. Open the Multiple Ring Buffer Tool – ArcToolbox >Proximity >Multiple Ring Buffer

2. Fill Inputs

• Input Features (Points, Polylines, Polygons)
• Output Feature Class
• Enter each buffer distance.

The remaining entries are optional.

The new output layer from the buffer will be added to the map.  Notice that I have used the dissolve option.  This causes the buffer rings to dissolve based up distance.