I need to start with good shoes... Trouble is, they have to be good in mud too... I do half my work outside in slip on rubber boots without even a liner in them.
Oh well, the muddy season is nearly over I suppose, at least for awhile ;~D.
Timberland makes some good work boots. I've got a pair of steeltoed ones that I use here at work when I have to go out in the plant. They're heavy, but they have good support. I got them at a discount shoe store and they were actually men's shoes, but hey, I don't care as long as they fit reasonably well.