Oldbat-never,
This is always an intriguing part of the postseason. Unless things have changed, there are 9-10 different items that the coaches need to agree on when determining the makeup of a series....and if agreement is difficult to come by, then coin flips occur. After the local rounds are complete, these "coin flips" may have to occur over the phone -- a sure source of texas (urban) legend. In '02, Plano East hosted a one-game "series" at our field when Coach English asked the Marshall coach whether the zip code of some poduck west texas town ended in an odd or even number.
Obviously, the key issues are 1) one or three game series, 2) site (home & home, neutral site, or combination), 3) umpires -- usually divided between home/2nd & 1st/3rd, 4) game dates & times (Thu, Fri, Sat -- or Fri, Sat DH, etc.). In addition, there are issues like what baseballs to use.
A coach friend of mine once had to participate in 10 coin flips -- versus a particularly belligerent coach that was quite displeased with the idea of a one-game series. Strange things happen.
Others -- post the stories you've heard -- some are quite intriging.
-PD