Where do I find more of these? Are there descriptions of them in some of the books or do they expect me to make them? If I make them how do I know before that it may be "overpowered" and have to be the bad guy and "acquire" it from the PC.

Ship components can really only be found in the Core book, Into The Storm, Battlefleet Koronus and Hostile Acquisitions, although there are a few unique items in Faith and Coin.

If you mean are you as the GM supposed to make them then sure if you want. They are meant to be extremely rare and should be overpowered compared to normal items. If you find you make them too powerful, have it randomly break since no one really knows how to perform maintenance on it and they have to get it repaired.

There's also a generation system in Stars of Inequity that will allow you to modify standard components into archeotech versions.

Archeotech ship components in particular should really be "Quest Goals" rather than something bought or found along the way. To that end though, they're also there to break the system. They're the "Magic Items" of the 41st Millenium more than psykers are. They should do something wondrous, and even incomprehensible, like a laser Macrocannons battery that only needs 1 power, or voidshield generators cannot be overloaded, they simply shut down for an extra turn instead. By definition they're overpowered, but they make up for it by being Unique, Precious, and generally requiring players to seek them out specifically instead of gaining Profit.

Stick to the ones in the book until you get the system down. Really. Most broken games are the result of happy GMs going beyond the basic rules before they understand the system.