me being the least likely person to get this thing right... is there any place for someone with little knowledge to find instructions on putting together the system I described above?
You've given almost no details about how it's going to work. Given your question, I guess this is because you don't know yet.
I suggest that you start by deciding what sort of technology you're going to use to enable the sensor to detect the presence and identity of the associated 'key'. Then work out what hardware you'd need on the sending and receiving side for that technology to be used, and source the hardware for a prototype. You will also need to decide how you're going to operate the bolt. If you use a solenoid, you need to identify one that has enough force and throw to operate the bolt, and find out what voltage and current it requires. It's not clear whether you want to operate the bolt in both directions. If you do, then note that not all solenoids work in both directions. If you do use a solenoid, you'll need a driver circuit to control it. An H-bridge motor driver with a suitable current and voltage rating would be the easiest solution, but there are lots of alternatives. You might consider using a servo instead of a solenoid - in this case you would not need a separate driver circuit since the servo takes care of all that for you.
You might have some circuit design to do - you could use a solderless breadboard for that or build it up on stripboard. I guess this will include an Arduino on the receiving side. Then learn how to use an Arduino, starting from simple examples and working up to your own sketches. Learn how to do each of the things your solution needs the Arduino to do. Once you have the parts working, start bringing them together to form your overall solution.
If you tackle this one step at a time, there's no reason you can't do this. If you get stuck, there are plenty of people here to give you suggestions of how to tackle the problem. (However, don't expect people to do the work for you, unless you're willing to pay them for their time.)