Geek squad rips people off. They will sell you things you don't need(taking advantage of the not tech savy) and charge you a buttload to just connect a few wires. I had a friend that worked there. Thats beside the point of the thread though and honestly a job is a job.
Try googling. For computer hardware the internet should be your first choice there are sooooo many sites that will help you. http://tinyurl.com/26brqtr
I would also look into books. 70% of anything I wanted to learn, I learned from a book. Networking, Cpu structures, Computer components, etc. I would buy a "for dummies" book and try there. (Don't pay full price though, try getting used or something.)
have you ever got any electronics repaired? the whole thing is based on taking advantage of people that dont know simple trouble shooting.
I would look at getting a+ certified or taking an a+ book, it will give you a certification that should make a geek squad type job an easy hire. as well as teach all the basics and some more in depth hardware and software concepts.
programming classes etc really can help when troubleshooting, believe it or not. i thought it was a useless class to till i took it and learned alot about how programs work, where errors and conflicts occur etc etc.
i am 2 weeks away from an AAS in computer support, and a few credits away from a network admin as well.
even if you dont know how to do most of the stuff they may still hire you if you are good with customers, and can do basic installs, recoveries etc such as installing anti vrius or anti theft software on new pc's