if the course you are planning on building the tee signs on is fairly wooded then i wouldn't use anything else but what I found in the forest. Use 6" diameter trunks / branches for the post, cut the top off on an angle. If there are any fallen trees (preferably hardwood) slice the trunk (at least 12" in diameter) down to 2" thick pieces and use these as your signs. Burn or carve your hole information (as said above) onto the signs, clear coat with a lacquer and mount to the posts. I personally think these look the best if done properly. Fairly cheap for materials as well, might take some time though.