For most structure lighting you will want some of the inverted cone type LEDs though, the usual rounded LEDs have a rather narrow viewing angle. The cone type spread the light much more evenly. A good way to get them is to pick up LED CHristmas lights at the end of the season - warm white is the most useful. For smaller lights such as an outdoor light over a doorway, you cna use the normal LEDs if they fit, or surface mount ones to fit in really small places.
Even if you use incandescent bulbs, use DC power, at about 20% less voltage thant he bulbs are rated for. Bulbs last longer on DC since the current is continuous, and last significantly longer when run under their rated voltage. And keeping them dimmer eliminates the "Doc Brown is playing with Mr Fusion in the kitchen" effect of an over-bright light bulb.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
I recommend that you use DC and LED's as they last longer than bulbs.
Since you have a computer, Goggle is your friend for finding all sorts of information. However, as a general rule, use a 1000 ohm resistor in series with either lead of the LED and connect it to 12 VDC. The long lead on the LED goes to positive and the short lead goes to negative. If you connect it backwards it won't light up, but at the same time it is doubtful that you have damaged it. Just reverse the connection.
Elmer.
The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.
(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.
I want to put some lights on my HO layout. There will be some traffic signals, dwarfs and some lights in buildings for night riding. Should I go DC or AC? "Regular" bulbs or LED? The main problem is that i don't know much about electricity. Any good reading source about the topic? Or former MR article?
Guy
Modeling CNR in the 50's