Kermode as the Principles of flt bible
I find Kermode's book to be a bit thrifty on details to be honest. I've delved into it lots of times with a question and come out of it frustrated and looking at the price-tag, cursing. You'd probably need a more spacecraft orientated book to deal with that sort of question.
It can be calculated by equating the kinetic energy of an object to the gravitational potential energy of the point in the field which the object is in. It turns out to be independent of the mass of the object and is equal to twice the gravitational constant times the mass of the Earth, divided by the distance from the centre of the Earth to the object. This is all then square rooted.
As for the ladder idea, of course it would work in theory. Build the ladder 36,000 km high and you'll be in a geostationary orbit anyway and won't have to worry about gravity.
Ginger
