Cannot upload to Arduino Ethernet with Arduino USB Serial Light Adapter

I have an Arduino Ethernet and the Arduino USB Serial Light Adapter.

All of this gear arrived today; I’m brand new to Arduino. After several hours of frustration I’m ready to send it all back, but I’m hopefully someone out here can help me.

I am trying to upload the basic “Blink” program to test this board. I’ve figured out that I need to change int led = 13; to int led = 9; since pin 9 (not pin 13) controls the LED on the Arduino Ethernet.

All that being said, the upload fails with this message:
avrdude: stk500_getsync(): not in sync: resp=0x00

I’ve researched this and learned that this message means there’s a failure communicating with the Arduino board.

I’ve checked my settings… the correct Board and Serial Port are selected. See attached pics for details. [Apparently you have to be logged into the forums to see the attachments.]

I’m running on a Mac with OS 10.7.5 and am using the 1.0.4 Arduino IDE. I have a USB cable plugged into my Mac. It’s connected to the Arduino USB Serial Light Adapter, which is plugged into the Arduino Ethernet. The Mac appears to see the Arduino USB Serial Light Adapter, per the attached screenshot so I don’t think it’s a bad cable.

Any help or suggestions would be greatly appreciated. Thanks!

For what it's worth... I was never able to get my board to work. I sent it back and got a new one, which is working great so far.