I purchased some blank atmega328s a while ago, and having used the pair or programmed parts I also bought, and all the promini's I bought, and the 2 atmega328s I had on two duemilanoves, I was finally out of options and had to learn how to use the blank ones.
So, after a bunch of fooling around, I was able to get the Bit Bang method here working
Made up a X3 to ICSP cable, added pins to the X3 connecter, downloaded , unzipped, moved files as directed, then downloaded some more to get the avrdude.conf file that include the 328P. Set the fuses for the 328, wrote those okay, then burned the optiboot for the 328, verified it, wrote the lock bit. Unplugged everything, opened the IDE and tried to download the blink program. Couldn't do it. Tried several times with no luck, lots of reset pushing at different times & lengths, just the dreaded Not in Sync error (the one that ends with 0051).
Went back, unlocked the part, cycled power again and downloaded the standard bootloader for 168-328. Set the lockbit, unplugged and replugged for the IDE, and this time Blink downloaded okay.
Not sure what the problem is with optiboot & downloading, but I have a working method anyway now.
Hurrah! Good feeling, eh?
(The part that worked. Not the bit about Optiboot. That's got to be annoying.)
Um, I heard there were TWO Optiboots, one for Uno, and another for ??? older boards. Maybe??
That only seems to be an option for the Diecimila/Duemilanova boards, not the Uno?
The Uno doesn't seem to have the equivalent of an X3 connector with CTS, DSR, DCD, and RI signals (all generally Modem control signals).
The ATMega 8U2 chip has unused pins so it would seem to be expandable to add that functionality with some jumpers to a connecter and the proper programming.
Its possible I had the wrong optiboot, being my first time sussing the process out.
I also struggled with my Arduino-0021 folder seemingly disappearing, Windows Vista had it in some Virtual Program Files area or something, was a bunch of aggravation to find it and get it back under C:.