If you're into this type of stuff check out Smash the stack[1] It has a bunch of memory type vulnerability wargames (specifically the IO level) for your choosing. They start off basic, like the one you presented in the blog, then more advanced topics like heap overflows, return 2 libc, SEH overwrites, GOT overwrites, ROP techniques etc. like WestCoastJustin pointed out phrack has phenomenal articles but require you t…
Smashthestack and overthewire both have a wide variety of wargames that might be fun to look into if you're interested in pursing security related challenges:
smashthestack - http://www.smashthestack.org/ overthewire - http://www.overthewire.org/wargames/
There's also an intro level CTF going on for another 9 days @ http://zeromutarts.de/
Registration is easy and instantaneous.