You're running a 30 amp circuit? That seems a bit off to me. I would have expected a 15 or 20 amp circuit....actually I would use one 20 amp circuit if it were me. 15 amp circuits are what most of your in house outlet are wired for. Then thinks like your frig (dedicated appliances), kitchen outlets, garage outlets, basically anything that might have a device plugged into it that requires more "juice" would be on a 20 amp circuit. If you do end up running that 30 amp circuit then you have to make sure you size your wire accordingly. A 15 amp circuit requires 14 gauge wire, 20 amp requires 12 guage wire, 30 amp circuit I don't know. Is your 30am circuit really 2 15 amp lines?
I am not an electrician, but I do like to pretend and have wired several houses (mine and some friends). So my advice, 20 amp circuit, use 12 gauge romex, use outlets approved for a 20 amp circuit, outlets should be 3 feet from the floor and ususaally no more than 12 feet apart. For safetys sake I would run the line first to a GFCI (20amp) outlet and then everything else should be wired off the GFCI so all down stream circuits/devices are protected for shock hazards. The line run to the coup, if underground, should be a of a type meant for burying (usually it's grey and not white like normal household romex wire). Now this part I am not sure of, but I wonder if it wouldn't be a good idea to sink a separate ground rod just for the coup for added safety. I am not sure about that one and it should work either way. I hope that helps some.