I am just getting back into building models after a close to 15 year vacation from it and things have changed a lot.  One of the last models I built back then was the enterprise D with fiber optics.  Lighting models is very different now.  You can get kits, for this, and spend a lot of money, or get the parts yourself and save a lot of money while learning about basic circuits.

While doing research on LED's I came across this site:  http://led.linear1.org/led.wiz

Give it your parameters, and it will design a circuit for you.   It will even tell you what resistors to use too.  It can't do anything complex like blinking or strobing, but for basic, steady on circuits, it works great.

In addition the page about basics will answer common questions about LED's:  http://led.linear1.org/category/led-basics/