Not balanced or unbalanced microphones,more like the cables used to connect the microphones. a balanced cable contains a 1/4 inch balanced plug ( tip,ring sleeve) or XLR connector (with 3 pins )which contains a hot lead for grounding.
Unbalanced cables contain a 1/4" plug that contains only a tip and sleeve.
Most cheap mics (Radio Whack comes to mind) comes with unbalanced cables for connectors, though balanced XLR and cables can also be used (as evidenced by the 3 pins at the bottom of the mic)