Recover from android factory reset? I "accidentally" did factory reset my sister's phone. I'm interested in trying out AccessData FTK Imager but the problem is i don't know how to load the android filesystem for insepection?

Or more broadly, how to recover from factory reset. No backups, no google sync.
There is no way to roll back a factory reset. There are, however, ways to recover data from the internal drive. 

As always, if your are dealing with a potentially catastrophic loss scenario make a copy of the current state. The time-tested way is to clone the state by using dd via the adb (Android Debug Bridge) tool from the Android SDK. Guymager may be an alternative but I haven't used it for this purpose yet.


Here is slightly out-of-date how-to using dd. 
Here is a how-to that only relies on Android tools.(Android 4+ only)


After creating a clone you can attach the phone to a PC and try your luck with Testdisk or the less powerful but easier to use Recuva (MS Windows only). If this is not working out, bring in the big guns.

Get a copy of Paladin (it includes Autopsy/Sleuth-Kit, a powerful forensics tool) and start digging. Be warned, this can take a long time.