Being a Florida native for 29 years before moving to California, I will chime in here a bit. It depends on what bug has got you. And, as we all know, Florida if full of bugs. For mosquitoes and no-see-ems (very small bugs that you can barely see that are often flying around your face at dusk) the ammonia and other anti-itch creams work okay. Basically the little bugger injects an anti-coagulant when it bites and that is what is irritating your skin.
Another nasty bug is the red bug. This is a little bug that I think belongs in the spider/tick family (not sure about that). This little bugs actually burrow under your skin, so that the red itchy bump you have actually contains a bug. To relieve the itch, you must kill the bug. Most everyone recommends clear nail polish applied on the bump. This prevents air/oxygen to the bug and it dies. Gross, I know.
I suspect the person who rode in the hay ride and the person who had bites around their ankles may have had the red bugs. Also, for the person who complained of a rash, sometimes you can get a rash from sweating and having skin rubbing together when you are doing a lot of walking and running, such as between your legs or under your arms. Long distance runners get this a lot. One way to combat that is to put a lubricant on those spots before you go out, such as petroleum jelly. Running stores will also sell a product specially design for this purpose that may be lighter and less greasy than petroleum jelly.
Hope that helps.
Michele