Tigerdude,
Unfortunately they don't put it out in a "package". Here is what is required to complete the kit, this is taken directly from Tower's website
Engine: .40-.46 (2-Stroke)(with bearings) or .56-.65 (4-Stroke)
Radio: 4 Channel
Servos: 5 Standard
Servo Extensions 6": 2 (ailerons)
Covering: Two 6' Rolls and Paint to match
Misc. Items: 2-1/4" Spinner, Two 2-3/4" Main Wheels, One 1" Tailwheel
Propeller, 8 oz Fuel Tank, Fuel Tubing, Building and Field
Equipment.
The LT-40 kit is a rather odd duck in the hobby in that it came with everything you needed with the exception of the engine and the radio. Very few kits are that complete. The biggest reason for that is that most kit builders will have their own preferences of what types of wheels, spinners, fuel tank, etc. that they want to use. With the ease of Tower's website though you can have it all come to you in one very complete package.
There are plenty of people out there that will give you all kinds of recommendations on what type of engine to use in this plane ranging from a bare bones 40 all the way up to a Chevy Small Block. But my choice would be the OS 46 AX (I actually use the FX in mine, but those aren't available any longer). It is plenty of motor for the plane to fly with. No, it won't "3D", but this plane really isn't designed for that anyway.
Hope this helps
Ken