i use the flat webbing tow strap stuff, it works really well, can be made to any length and have hooks fitted if you like. some people use kenetic rope but i dont like snatch recoveries on my 1884 LR90 as im worried my rear x-member will get torn off due to its old age!
shackles... think the standard is 3.25ton. could get a 5ton if your worried. basically you have to add up the total vehicle weight, and then some more because obviously your stuck!
most of all, make sure you have good recovery points, otherwise you risk tearing off all your panels and chassis parts. jate rings work really well if you have the holes predrilled into your chassis.