My StreetPilot doesn't have the GeoCaching icons, so I use the Information Icon (? inside a box) to indicate caches. I haven't been marking them found, but I probably should start as this quantity gets larger!
I mark moving caches with a car icon, that way I recognize it before I start a search. If I have just checked the latest co-ordinates on a moving cache, it is OK to search there. I mark my car with the parking lot icon.
A friend's house I have marked with the restaurant icon. They cook GREAT food