roll back OSX 10.9.1 to 10.9

Not really.  Time machine is used to make regular backups of your system.  Rollback is then simple prior to your upgrade.

If you don't have backups there isn't really a way to downgrade.

the machine is actually a new build, purchased with osx installed on it.  there is no way to find osx 10.9?

You can try booting the machine with Command+R and go into the recovery mode.  Then whatever the default OS that the machine came with can be restored and you could work up from there.

I am unaware of a location to download older versions of Apple software now that it is all handled by the App Store.

oh man, that's ridiculous.  this is why i usually stay away from apple products.

If it came with 10.9.1 installed, then it might not even boot from 10.9.0. Apple products typically do not boot from system software older than they shipped with.

Why do you want to downgrade to 10.9.0 anyway? 10.9.1 was just a bug fix for 10.9.0. There is not that much difference between the two operating systems.

What problem are you trying to address? There might be an easier solution than downgrading the OS.

Apple delivers computers with their specific os. This means that the required software and drivers are updated for the new hardware. Thus you better stay with 10.9.1 if the new machine needs it, downgrading would otherwise be just going from bad to worse in this context.

Questions is why you would love to downgrade? Can you let us know why you like to downgrade? Especially from 10.9.1 to 10.9?

I am using specific hardware that does not yet have drivers for 10.9.1.  (http://duc.avid.com/showthread.php?s=65e4504f322bec89eb5ea199664a017e&t=349150)

Since I bought the MacbookPro new, I have no option of using time machine to go back to a pre-update OS.  It seems my only option is to somehow get ahold of an older OS and reformat.

Your computer might not run at all on an older OS. If you can get a copy of 10.9, I suggest you install it on an external USB drive first and see if it will boot or not.

Pretty unprofessional of Avid not to keep their product up to date.

It seems you can't buy OS  10.9.0 online any more. The only resolution I can think of (other than waiting for Avid to pull the finger out) is to find someone with a Mac running OS 10.9.0 and use their recovery partition to install 10.9.0 onto a USB drive, or create a USB installer:

http://www.techrepublic.com/blog/apple-in-the-enterprise/how-to-create-a-bootable-usb-to-install-os-x-mavericks/

yeah, this is so frustrating.  Avid has definitely dropped the ball.  Yet Apple is absolutely NO help either.  I can't find 10.9.0 anywhere.  And, additionally, I would have to pay to download Mountain Lion.

Mountain Lion is less likely to work with your computer than 10.9.0. Do you know anyone who is running 10.9.0?

i just got off the phone with Apple tech support and their official line is that "downgrading to a previous OS is not supported" and will "mess up my computer."  Basically, they claim that if I install anything other than osx 10.9.1, the firmware could break my logic-board, etc.  They also claim that osx 10.9 has been completely erased and no one at apple has it.  haaa.  Mac geniuses.

i don't unfortunately.  :(

i may have found someone with osx 10.9!  How should i solicit getting this OS from them?

That might work, juist check everything! You loose Some system software that comes with your hardware!