As of Version 9, all the functionality of the PlotLegends package is built into the Wolfram System.
PlotLegends added a PlotLegend option to a number of functions for creating legends. A native option, PlotLegends, has been added to the Wolfram System. The Legend function for creating legends has been replaced by BarLegend, LineLegend, PointLegend, and SwatchLegend for constructing specific types of legends. The use of ShowLegend to add a legend to a graphic is replaced by Legended.
|PlotLegends||Built–in Wolfram Language function|
See the Legends guide for an overview of the Wolfram System functionality.