[Bill Musarra]

As Ron says, the companys like Painlwess, American Autowire etc. will get you started. I had never wired a car before when I started mine. The weather pack etc. are good ones if you are concerned with wet conditions. I plan to rarely if ever go in the wet, so that is not a concern for me. I have found groups of connectors on ebay for say 59 Cadallacs etc. They all use the same "56" connectors. They come with 6, 4, 3, 2, and 1 connectors. Run about $15 +shipping. Great for making dash disconnects. You will have to find some bigger ones for the starter circuits which use big wires. The "kits" will have them in with evewrything else. Its just when you want to add relays to a starter circuit for say a start button that will need the larger connectors.There will be lots of bags with the different circuits and connectors. Follow the directions. You will have to alter things like steering column connectors. The companys will send you diagrams for how to do it. If you want to add things like relays, there are sites on the web that will educate you about what relays are and how they work. Most will give you diagrams for how to link the relays to get them to do some neat stuff like starter interrupts or automatic door lock openers.
When you start out. lay out the wires, decide where you want the connectors, decide where your wires are going to be routed, hidden secured etc. Mount all the apliances if you haven't done so. Are they in their final resting place? Be sure..... Hook up the dash wires first. Leave the wires from the relays long. Use good terminal strips from Radio Shack etc. to hook up lots of relays etc. Get a small power generator of about 6- 10 amps. Use it to test the circuits seperately. Nothing like100-150 amps surging through a bad circuit to fry many wires next to it.
The last thing you want to do is cut the wires to lenght. So make sure you are happy with how things are laid out. Just take your time. I changed the routing of my wires two or three times til I found the right route for them.
There are lots of other things, but these will get you going, and get your brain to going.

Bill