A couple of tips on buying tobacco products:

-Find someone you know who works in a store that sells blunts, papers, what-the-hell-ever, and get them to sell them to you.
-Get a job working in a store that sells those things and sell them to yourself. Locally-owned convenience stores or grocery stores are best. Corporate-owned stores may require you to be 18 to work there. Check around.
-If you won't work at a store that sells them and you don't know anyone who will sell them to you, then just go from store to store, trying to buy. If they say, "no", then go on to the next one. When they say, "yes", then make sure you buy from them on a regular basis-prefereably when there isn't any other co-workers around. Try convenience stores around 8-10 PM.
-Be careful trying to do this with buying alcohol. Most people will turn you away for trying to buy tobacco, but they're more likely to call the cops if you try to buy alcohol, for obvious reasons.

Good luck!