Please tell me how I test an outdoor 110 receptical to see if it is protected by a GFI ?

You can get a GFI receptacle tester, similar to the one I included a photo and instructions for:

http://www.idealindustries.com/pdf/61051manual.pdf

Read any instructions carefully to understand how the tester operates and reacts for the various tests and results .

A gfi receptacle will have a test button that will trip the gfi. If it does not trip when pressed, the gfi is bad. The receptacle will also have a reset button.

If these buttons are not on the receptacle, the panel breaker may be a gfi breaker. It will have a test and reset button on it.

If neither the breaker or receptacle are gfi, or if there is no gfi breaker on the circuit, the circuit is not gfi protected (a gfi receptacle can protect normal receptacles from ground fault if the normal receptacles are on the load side of the gfi (they become de-energized when the gfi trips).

A method that I use to determine if a receptacle is wired correctly is I plug a power bar with surge suppression into the receptacle. It should have lights to diagnose an open ground or reverse polarity similar to the above tester!