About the model, the earlier F had a chrome base rail, the later models, which also include the F as well as the F1 and F2, uses black base rails.
Take a look at *bay and search for "Sinar F". There you will find enough large detailed pictures so that you can identify this particular camera.
The value of the camera does of course depend on the model, age and wear, so an F is (US) $200-300, while a nice F2 is >$500. The lenses should also be $2-300 a piece.
To sum up, given that the camera is a chrome base-rail F I would start with an offer around $500 or so. (If the camera is newer, or even an F1 or F2 I would offer a bit more.) Do point out that you intend to use the camera and learn LF photography, rather than just trying to make a few bucks from reselling the separate items at e.g. *bay.

Last, about the choice of camera. I personally use an F2 for my outdoors LF photography. While it's not the lightest or smallest camera around, it's very easy to use, compared to most other types and models of cameras around. It is also very easy to learn LF with, as it got built in gadgets for setting both DoF and tilt/swing with precision.

//Björn