I've decided to try for a baby, so how do I get the Depo-Provera shot out my system?

Time. There is no treatment to force the depoprovera out of your system early. The real challenge lies in the fact that there can be prolonged sequela from depo-p. Reports of 6mo to a year before return to ovulation and regular cycles has been listed. This does not always happen, you will have to wait and see, sorry.