I need advice for installing LED lights in the interior of my car?

So, I am totally confused when it comes to installing electrical things in my car. I want neon lights in my interior, but all of them seem to come with wires that I have no idea how to connect anywhere. There are also ones that plug in to the cig lighter spot but I dont know how I would hide the wires because my lighter thingy is out in the open. So I was thinking, why not just get an LED lightstrip that is battery operated and just stick it above the pedals? And with an on/off switch it would look even better. But my question is:

Where can I find an LED strip that is battery(not car battery) operated that is hide-able? and possible switch operated too? Please send me a link, I can't find any anywhere