MLB salaries, for individual players, at the team level (average and median), and at the league level (average and median). Three collections are given here in a single file: the late Doug Pappas of SABR, Rich Hill, and me. The "Oldies" are gleaned from a variety of different sources, typically mentioned in passing or as quoted in interviews of players. Files for the 1960s (and some of the 1970s) are from Selig v. U.S. and Rich Hill (1976-1977). Pappas' collection runs 1985-2001. Recently, a consistent source is the USAToday.com Salary Data Base (thanks for the heads up go to Shaun Augustin). I've also included various reports of average salaries and "median payrolls" by team since they are much more like salary descriptives.
The files are all in MSExcel format. So, use your "Save Target As" command to save them to your hard disk.
Annually:
Averages, Median, Minimum