Low level programming ...

Hi everyone

Currently i am following a university degree program known as
'Computing and Information Systems'. So, our syllabus are more related
to topics like Information System, Data base management system,
Software Engineering etc..

But i am interested in system programming [low level programming] . I
am studying those subjects for getting a degree.

Basically i have some C knowledge ( not that much written a library
management program in Turbo C ). I dont know assembly language,
computer architecture or electronics [do i need electronics ? ].

So, where should i get started [i.e what topics like linux kernel,
process, threads] ? Note that i am self learner. Any suggestions ? Can
any one recomned a open source program to start with ?

Since English is not my native language, execuse my English

Thank you!