Thanks to DarkUFO reader John from Go Hawaii for the following.
Just took a Kos Hummer movie tour today. Lost is filming all week in the Ka'a'awa Valley. (Hurley's golf course, plus many other scenes filmed there.)
There is a large "army camp" set, a huge new tower which looks like an oil rig only in wood - maybe a well. I saw Locke and Sawyer for sure. Others spotted Juliet and reports were Hurley was on the set which makes no sense!
Source: Go Hawaii