Can a Gentile tell me Loshon Hara about another Jew?
Unless the information being listened to is directly relevant to you (e.g., to arrange a business deal or a marriage), this is prohibited. The Chofetz Chaim (6:2) makes no difference between a Jew and a Gentile
Even merely listening to Lashon Hara is a violation of the Torah, even if the listener intends not to believe anything while he is listening. Simply bending his ear to hear constitutes a violation.
The reference is to the listening, not to who speaks.