I am really thankful for your continued attention to my problem, but I think I'll quit this. I did stop the I/O line passing some time ago by using FF, canceling the FFFF instructed in the Ladyada>Xbee>connect tutorial. The avrdude sync error started happening again. I thought it had something to do with uploading when the Arduino reset was plugged into the transistor collector, but now it happens anyway. Arduino troubleshooting wasn't helpful. I've looked into the forums on this error message and the consensus is that nobody knows what to do about it, after so many posts.
Your efforts in open source and tutorials are heroic and hugely appreciated, but for the unwashed like myself, there are so many permutations of unknown problem sources:
Soldering is tricky---I bought 3 datalogger kits, out of my failure to get the first to work. Finally got two to work after construction by consulting the published circuits but they still won't light up the LEDs. Got the first one to work by grounding the SD card holder. Likewise, 3 Xbee adapters and all continuities were OK checked for all pins, but who knows? One out of three Xbees I bought won't let the adapter LEDs light up on the FTDI USB cable.
Who knows that the X-CTU has to be removed and installed frequently? It starts displaying the same serial number with different Xbees and says OK for connection with Xbees that can't connect. One must always check to see for the right serial #, otherwise lots of wasted time ensues.
Lots of things did work at first: I had great Xbee communication with the Ping distance sketch, temperature, etc. Perhaps this is where the components were injured. I really learned soldering skills, armed with paste flux, especially with those tiny wires to the RGB led belts. I learned a lot and am most grateful to all of you advisors.