I am a final year CS student, and would like to study info sec. Till today, I've been reading infosec mailing lists, some Phrack papers etc., but all in a very casual way.
I am interested in learning security in depth, and have gathered that there are some courses like Network+, Security+ etc that provide good exposure. But such courses are not an option for me due to the cost.
How do I really start? Please provide pointers to any online resources if possible. As said earlier, I'm a CS student, and am pretty confident with my programming and networking.