If you are using any kind of wood it will rot. Pressure treated or not. If you do not use pressure treated and use regular milled wood that will rot very quickly and may harbor carpenter ants. Creosote dipped wood doesn't last long if in contact with ground. Much depends on the actual species of wood though.
BUT: If you have a nice straight driveway and don't mind pressure treated then use standard PT 4" X 6" X 16'. Can be delivered by any lumber yard. Do
make sure you get straight ones. Best to go to lumber yard an pick out the ones you want delivered.
Bricks or cobble stones are another choice.
Gilbert Block in Laconia/Belmont will deliver pallets of bricks, stones, blocks, etc.
LINK