This week, JustFlight released their L-1011 packages for FSX. For now, you can make it yours directly via download, and you can optionally add a livery pack. Note that the boxed version to ship in 2 weeks is not including the additional liveries included in this last package.
There will be another L-1011 competing product for FSX, this time developed by Captain Sim. But they’ve just published their first preview so we shouldn’t expect it in our hands so quickly.