Can sum1 help me out....

ive never tryed DXM before...... im from new zealand and ive never herd of anyone doing DXM in new zealand but anyways i have read alot of shit about it on this site and it sounds like a mean trip..... could u please tell me where to get DXM from, and Robotussin the cough medicine gives u a buzz? i have a bottle of robotussin (syrup) so am i supposed to skull back the whole bottle of it to get a buzz? and also does dymetap cough medicine give u a buzz?
sorry for all the questions but im new to these sort of trips or buzz's.
Thanks alot :o