If you're talking about
only PC, basically your only choice is the MLB 2K series.
Be warned though; it's not very good. MLB 2K13 has been WIDELY panned even more than the rest of the series. Nowhere NEAR full price. 2K12 is a much better option, with updated rosters and a good set of sliders.
If you're looking for a "management sim", and don't care to control the on field action, and also don't mind the lack of MLB license and players, check out "Out of the Park Baseball"
http://www.operationsports.com/reviews/708/out-of-the-park-baseball-14/
****ALL THAT BEING SAID*****
If you have a Playstation 3, or might be able to get access to one,
BY ALL MEANS, GET MLB THE SHOW.
It is, far and away, hands down, not even CLOSE, the BEST baseball sim/game on the market: leaps and bounds better than the 2K series.
But if your only option is the 2K series, please do NOT pay full price for it.