Kryzco has the right idea... on Clark there are a number of good places. I would suggest Secrets (on east side of Clark just north of Belmont) as a good place to start, and if you mention that you have "that 20% off paper" at home from the last time you visited but forgot to bring it they'll give you the 20% off on the spot. Another good place to check is pipesandstuff.com (a brick & mortar store despite the name) which is also on Clark (west side of the street) but is just south of Belmont.