For most buyers, price (and therefore, multiple) is based on a fomula which takes into account each buyer's desired equity returns, their particular borrowing costs, and their projected NOI. Unlike apartments or office buildings, golf courses have large issues out of the control of the owner such as weather and management, which make NOI bounce around a bit. For this reason, while multiples are good rules of thumb, they need to be taken with a grain of salt.
Historically, golf courses have generally traded in the 8-10x range depending, as Jeff pointed out, on the potential for growth. They got a bit crazy in the late 90's when 11x and higher were the norm, but things appear to be back to normal, although many deals are still happening at the 10x+ range.