Wiring

After my recent crap w/ my car and it being an auto i've decided i want a killer sound set up. problem i have minimal knowledge about audio but would like to purchase and install my own setup looking to up grade components and install 2 10" subwoofers question is how hard would all this be??? and can anyone here either give me instructions or direct me to the right spot?? also will i need to upgrade my alt cause i dont see waiting for it to die to be a smart option comsidering that might leave me a little stranded!! Any and all help would be kewl. thanks in advance