Hi,
there are different sources for gears.
I catch the demage toys of my son. Sometimes there are very intersting gears inside.
Old watches also a wonderfull "gearsource".
Some cameras have also interesting parts.
To get a small motor dissasemble a photocamera or a cellphone (the vibration alert is using a fine motor, also the winder of a camera).
Servos also use fine gears.
Some electronic stores have a own repair service. Just ask here to have a look in their box with the finaly demage parts.
But only disasemble the demage parts. To disassemble the new camera or cellphone of your sweethart maybee a mistake ;-)))
best regards
Thorsten
www.mikromodell.de