not to put too much of a downer on the idea, take a look at some sucessfull landscape photographers web sites and see what they do and then emulate in your own style. I think you'll find the two brits grafted for years to get where they are. And I think Quang-Tuan Luong photographed all the US National parks before he gave up his day job to make his living purely from photography.

So it can be done if you have a mind and the will to do it.

http://www.joecornish.co.uk/

http://www.charliewaite.com/

http://www.terragalleria.com/