While the buffer wizard is not exposed through ArcPy, geometries do expose the buffer method so the following works to create multiple ring buffers:
def MultiRingBuffer(ringDistance, ringCount, inputLayer, outputLayer):
buffers = 
cursor = arcpy.SearchCursor(inputLayer)
for inputFeature in cursor:
sourceOid = inputFeature.getValue("OBJECTID")
currentBuffers = dict()
prevBuffer = inputFeature.Shape
for multiple in range(1, ringCount + 1):
distance = multiple * ringDistance
bufferedGeom = inputFeature.Shape.buffer(distance)
bufGeom = bufferedGeom.difference(prevBuffer)
prevBuffer = bufferedGeom
row = dict()
row["sourceOid"] = sourceOid
row["distance"] = distance
row["SHAPE"] = bufGeom
currentBuffers[distance] = row
cursor = arcpy.InsertCursor(outputLayer)
for ringBuffers in buffers:
for feature in ringBuffers.values():
row = cursor.newRow()
for k in feature.keys():
if k == "SHAPE":
row.Shape = feature[k]
if __name__ == '__main__':
MultiRingBuffer(10, 10, "c:\\temp\\test.gdb\\buffertest", "c:\\temp\\test.gdb\\bufferout")
For each source feature, we create a dictionary to store each ring buffer. Each of these buffers is a dictionary with a few values - the source OID, the distance, and the buffer geometry. We then create an insert cursor and create features in the output table for each ring buffer of each input feature.
Edit: I have tested this and with 3 simple features, where the gp tool takes over a minute, this script takes ~1s once arcpy has finished importing.
Edit 2: Fixed a couple of bugs - firstly, the difference call was removing the previous ring rather than all previous rings. Secondly, I wasn't adding the ring to the currentBuffer so it wasn't getting added later...
Edit 3: Handled the shape field not being 'SHAPE' in the output featureclass. Added cleanup of cursor objects.