Atmega328P-PU: Programmer is not responding
I've read the tutorial at the crash-bang website and found two issues with it. The first issue is minor and probably won't fix your upload issue.

Step 3 says to connect +ve rail –> AVCC (pin 20) and +ve rail –> AREF (pin 21). You can leave those pins not connected. A really awesome guy named Julian ILETT has a video on youtube showing a homemade Arduino using the bare minimum connections needed. https://www.youtube.com/watch?v=sNIMCdVOHOM.

The second issue with the tutorial is in Step 5, "Connect the DTR pin of the FTDI, via a 0.1uF capacitor to pin1 on the ATmega.". A lot of people claim this works, but it doesn't work for everyone. It doesn't work for me and I have 2 of the identical FTDI programmers used in the tutorial. If you watch Julian's video starting at 12:48, you will see that he had trouble uploading a sketch using the DTR / 0.1uf capacitor method. He is using a different USB to TTL device but I have one of the identical devices he was using and the 0.1uf cap method doesn't work for me.

The solution to the upload issue is to use a switch to reset the Atmega328P-PU. Like the tutorial says, use a 10k ohm resistor connected to +5V and pin 1 of the Atmega328P. Now connect a one terminal of a N.O. momentary switch to ground and the other to pin 1 of the Atmega328P. To upload your sketch, click the upload button on the Arduino IDE window. As soon as the Debug window says "Binary Sketch Size…", press the reset button and hold it down for 1/2 a second then release.

I've just joined arduino.stackexchange.com a week ago so my answer may be a bit late. Hopefully this helps people in the future.