The minor leaguers don't come close to the money that the is given out in the major's. As a rookie you start off in single A ball and then move up thru the system, some faster than others, but usually takes at least a few years for the player to develop and get promoted.
Google Answers: MLB and Minor league Minimum Saleries
First contract season: $850/month maximum. After that, open to negotiation
Alien Salary Rates: Different for aliens on visas--mandated by INS (Immigration).
Triple-A--First year: $2,150/month, after first year no less than $2,150/month
Class AA-First year: $1,500/month, after first year no less than $1,500/month
Class A (full season)--First year: $1,050/month, after first year no
less than $1,050/month
Class A (short-season)--First year: $850/month, after first year no
less than $850/month