For a lift you have a lot of options. You can go suspension for big $$$$ or go with some basic lifts for a little cheaper. The cheapest way would be to go for a shackle lift with a TT in the front while changing your rear leaf pack with a pack from a 4-door. This will give you about 2 inches of lift of so (probably a little less after settling with driving) all around. To that you can add a body lift ranging from 1-3 inches. Rough Country, Skyjacker, Superlift all make suspension lifts that you can use. As for tires that you can fit take a look here:
http://www.explorerforum.com/forums//showthread.php?t=67200.
Your locker options depend on what kind of differential you have as well. Limited slip or open. Take a look at the code on your door jam...
41 - 3.27 non-limited slip (Explorer/Mountaineer)
45 - 3.55 non-limited slip (Explorer/Mountaineer)
46 - 3.73 non-limited slip (Explorer/Mountaineer)
42 - 4.10 non-limited slip (Explorer/Mountaineer)
D1 - 3.27 limited slip (Explorer/Mountaineer)
D4 - 3.73 limited slip (Explorer/Mountaineer)
D2 - 4.10 limited slip (Explorer/Mountaineer)
Your best bet to find exactly what you're looking for is to so a search. Tons of guys here have made some badass offroad rigs