budget?
what kind of tasks do you want to do with a core i7 3770k?
do you already have a mobo with an intel chipset?
would you consider amd?
full pc specs?
for gaming, 3570k is a good, cheaper alternative.
for tasks that require use of 4+ cpu cores, 3770 non k (non-overclockable) may be good. core i7 3770 is the only desktop cpu with exact specs of 3770k. the onle thing missing in the 3770 is the fully unlocked multiplier which allows for higher overclocking.
here's a specs comparison of core i7 3770, 3770k and 3570k
http://ark.intel.com/compare/65719,65523,65520,69114
amd alternative may be amd fx8320.