RE: tracks in the mud?
As NHBuck said, "Big Bucks the Benoit Way" is a good book to start you in the right direction if you are unfamiliar with tracking.
Yes there is a difference between buck and doe tracks, but the difference will vary depending on which region you hunt. There are many variables to consider. Learning to read tracks takes time and commitment, and even the best of trackers are always learning.
If you are reading articles that say there is no difference between a buck and a doe track, you are reading very misleading articles.
I can start you off with some basic tracking tips, but the only way to improve is with experience, which means some serious footwork and the ability to pay close attention to detail. Snow is a huge benefit when it comes to tracking, but that doesn't mean that it is useless on bare ground.
Since you are talking about tracks in the mud, I will focus on that. First of all, you don't want to concentrate on one imprint. If the mud is quite soft, even a small doe might leave dewclaw prints. Is the deer running, walking, or trotting? It makes a huge difference. Therefore, look at where the other tracks are placed in relation to the first. A walking doe will not have much space (width-wise) in between prints. A mature buck will have more "staggered" tracks (if walking). If you see 4 deeply imbedded tracks close together (often overlapping), and then no more tracks until 10 or more feet away, this is obvioulsy a running deer (or, "on the jump" as we call it).
Big, mature bucks will have a much more flat and wide imprint than average deer. Where I'm from, big bucks will dress over 200 pounds,
and a big buck track is not easily overlooked by an experienced hunter (as DelcoJim pointed out). I realize that each region is different, but I also feel that every deer hunter can benefit from identifying and studying tracks more closely.