smutek,
good luck for your task!
it's actually little less than a year since i quit - because i had to prove myself i could, because i realized how nasty product the cig companies have in their hands (once they manage to sell a few packs for you, they start getting a steady cash flow from you... and it's all legal)... and because the habit was starting to feel not-so-good-anymore and it was one reason i was somewhat depressed back then.
the first few days were the most critical but maybe not the worst - i had to keep my hands full of interesting things to do all the time so i wouldnt've thought of cig breaks. having long bike trips, making really crappy tracks, etc.
after that it helped to be proud of the achievement so far and not to give up even if i slipped (i think i smoked half a pack or a pack being very very drunk at a halloween party something like two months later... but next day it was none again)
i can't say i have any more loose money after quitting (but i do eat better food and buy more records and "toys"
) but after quitting i managed to start swimming, jogging and all that again and now i'm hopefully a bit healthier and definitely somewhat less depressed than i was a year ago. i can't say if it's been a big improvement or not but at least more of my money now goes to the peoples' pockets who deserve it... like ableton