My advice won't help you much because even though i live in a very wet environment (seattle), my tie rods are still not at all rusty, and even though the adjuster was very hard to loosen, it still loosens up just fine and can rotate easily.
Changing out a tie rod is actually quite easy, if it's not all rusty like yours, but i'll run thru a quick explanation anyway of how i do it.
Now, what i do first is count, with a pick, the amount of threads that are showing from the tie rod to the adjuster before you loosen anything. When you go to put the new one in, is should have roughly the same amount of threads as the old one, so this way you can get the alignment back very close to where it was, so that at least you should be able to drive it to the shop to get a real alignment.
Loosen the adjuster (takes 5 seconds

), then remove the pin and undo the crown nut from the tie rod you want to replace and use either a fork, or a one of those ball joint removal tools, and pop the joint out of place.
Unscrew the tie rod out of the adjuster, holding the adjuster in place, then install the new one. Set the joint end up in place, then make the necessary adjustments to get the amount of threads back to where it should be, and you're done.
I did this on a friends Jeep Cherokee to replace both inner and outer tie rods on both sides of the vehicle, and the alignment was so close when i was done that the alignment shop was wondering why he thought he needed an alignment. It sounds like i was making that up.
Over a year ago, i pulled the entire steering linkage setup out of a junkyard so that i'd have spares for everything, including the idler arm. It was less than $10 because they charge by the foot. I may sell it one day, as i haven't needed any spares, but this is a great idea for anyone that sees it in a junkyard as a "I may need this one day" type of purchase.