Ok... here is the list of things you asked and their answers
1. glass - call glass shops, yellow pages become your best friend. The pricing will differ with where you are. I've seen people post that they can get one set of glass sheets for real cheap and others say that it cost them twice as much. Just shop around a little. You'll have to call then and ask for the in-house edge work, so it isn't really sharp and cutty.
2. plastic sliding glass track - get them at home depot if you're lucky. maybe even lowes. if not try rockler.com
3. caulk - depends on what you are keeping. Lets say you need lots of humidity... you are going to want to seal the entire inside of the rack/cage with something like Envirotex Epoxy and then use some 100% Silicon on the edges. Basically the trick is to let the epoxy and silicon cure fully. If you are doing a species that doesn't require much humidity... well then i'd still suggest the 100% Silicon, but basically use what ever will stick to the medium you are using.
4. wiring a light inside - what kind of light? a florescent tube needs two main things. One is the ballast and the second is the connectors. Most florescent fixtures you find in stores will have a built in ballast, while some reptile or fish tank ones will have the ballast somewhere on the cord so that you can mount it outside, behind, or on top of the tank. These can just be mounted to the top of each cage area, and have a wire run to the side, or to the back, your preference. A hole will need to be drilled for the cords to go through. this is where it gets "interesting". You can chop the plug off the end and have a very small "fitted" hole that will prevent any possible escapes by the inhabitants. The other option is to get a larger grommet say about 2inches that allows you to have several cords running through it with only one hole needing to be drilled. Its basically your choice. I prefer the 2 inch grommet for the multiple cords. Now for an incandecent light fixture... some florecent fixtures have incandecent built in with it... even if you have that you need to consider how you are going to keep the animal from getting burned and where the fixture should be positioned. A small ceramic incandecent socket should have 2 or three wires or places for the wires to connect. Bascally just connect like colors to like colors, very easy to do. You just need some plugs for the ends of the cords.
Thats about it... i'll reread my post in the morning and make sure that i said everything right... need some sleep right now.
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Later,
WhisQuila
