I am constructing a reflector receptacle from a 20 by 22 inch satellite dish with curved mirrors. My goal is to track the sun and collect optimal energy.

The Dish itself weighs 20 lbs, but once my team and I add the solar panel mount we guessed the total weight will increase to about 25-28 lbs. We are all CE's and we are having a hard time figuring out the proper electric motor to invest in.

How much torque and power is needed to rotate our receptacle?

Since the sun moves quite slowly you need very little power or torque. However, if you want the ability to slew the dish at some higher rate of speed it will boost thepower needs. Also I suspect that most of the power needed will be to overcome friction in the bearings, not for energy required to move the dish itself. If you can provide an estimate of the friction in the gearing we could provide a better analysis. But for a ballpark estimate - consider the motors that are used by amateur astronomers so that they can track the heavenly bodies they study with a telescope (the same problem as your). A typical telescope may weigh 50 pounds or so, and the motors that are used in these mounts are typically rated at 12 VDC and 3 amps or so, so say 60 watts power. See for example this mount:
CGEM DX Mount & Tripod Computerized Telescope [item # 91528] (http://www.celestron.com/astronomy/celestron-cgem-dx-mount-tripod.html) Mounts like these are already fully equipped with appropriate gearing and computer interfaces for tracking the sun, so perhaps you may want to consider using one of them instead of building your own?