I am rewiring a large part of my car through adding G3 alt and H4 headlights and wanted to add new connectors to the headlights for example. where is a good place to find specific connectors like this?
I believe MSD sells waterproof, multi-pin connectors (2,4,6,8). I used them on my sequential tail light kit from Scott Drake because I did not like his crimp on connectors. The MSD connectors really make a clean installation and easy future maintainence. I believe Summit Racing and Jegs sells them.
The best thing for your H4 headlights is to wire them up using a relay harness kit, available from Summit. This will give you brighter headlights and will reduce the electrical load on the switch. Use the SEARCH function to find threads regarding this, it has been covered well.
I wired my whole car from scratch. I used several sources for all the parts
Waytek wire (waytekwie.com) has weathrpack connectors, molded connectors, relays, and just about everything you would need to wire a car, except headlight connectors