Problems Getting Sketch Uploaded

I just purchased an Arduino Duemilanove. I am totally new to it and am trying to use the Getting Started guide located in the Tutorial section of the Arduino.cc website. I get all the way to the part where I need to run the sample "Blink" sketch.

I am running Windows XP. When I try and upload the sketch, I get this error:

avrdude: stk500_getsync(): not in sync: resp=0x30
avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51

Any help would be appreciated. I am totally new to this and am just trying to get the "Blink" example sketch to run at this point.

I am having a similar problem. Except this is the error it spits out:

Problem uploading to board

avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding

Im on a PowerPC, Mac OS X 10.5.6

Iv had this stuff working before, I'm a bit rusty, but any help would be much appreciated.

A common cause of this type of problem seems to be the wrong board and/or CPU type selected from the pull-down menu.

I have the correct things selected. I will keep trying things though. This is getting discouraging. I have an ATMEGA 328 if that matters.

I am having the same problem as the OP except I did originally have mine running for a while...

I am having the the same problem, with the same error messages, except I am using an Atmega168. I have checked the various suggestions, everything appears OK except it won't work :-[

@wolvie: try to reinstall the FTDI drivers. Under Mac OS X you first have to uninstall the drivers... see chapter 2.2 here:
http://www.ftdichip.com/Documents/InstallGuides/Mac_OS_X_Installation_Guide.pdf

and then install the latest VCP drivers from this website:
http://www.ftdichip.com/Drivers/VCP.htm

and then of course restart the Arduino IDE and select the correct serial port from the menu.

Did you install the D2XX Direct drivers in the past? Maybe you tried the Arduino BitBang hack? This disables the virtual com port I guess...

@hopsicle: Just to be sure:
Did you select the right serial port (e.g. COM6) in the Tools->Serial Port menu?

And did you select the right board (in your case: Arduino w/ ATmega328) in the Tools->Board menu?

Try to install the latest FTDI VCP driver (link see my last post). Is the Arduino directly connected to your PC or is it connected to a hub or keyboard or something?