A lot of people know this one but apparently not so many that there isn't a special tool you can buy or rent for $60-100 from Advanced Auto, AutoZone, etc.
Tie-rod end separator thingy to get stuck tie rod ends out of knuckles (only works for bottom mounted tie rods). Many times I've had the end with the nut just spin continuously but not want to come out of the knuckle at all.
One short piece of 2x4 and a bottle jack. Jack the 2x4 up until it hits the bottom of the tie rod and then give it a pump or two more. Try the nut now. If it won't come off pump the jack a time or two more. Soon (before you're lifting the truck up obviously) you should be able to just spin the nut off without the shaft spinning. Leave the nut on the end of the threads just a bit and whack the nut with a hammer a few times. It SHOULD drop down. Simply remove the nut and then the tie rod end should fall right out.