I'm looking to pay around $1 per bar, including shipping, and am willing to buy in 12-bar or 24-bar boxes.
I've found that Target (big US chain, similar to Walmart, but less noisy) has regular sales of 6-packs for $5, but the selection is relatively limited. It's where I buy most of my "regular" rotation items (great for breakfast/pm-work-snack/birdwatching-field-food).
Some grocery stores (e.g. "Wegman's" on the East coast, USA) have good prices on 12-packs.
Amazon has great prices on the regular Clif bars (particularly with "Subscribe & Save"), but has many complaints for selling nearly expired items, and doesn't (currently) have the seasonal bars listed (except by high priced 3rd parties).
I am considering buying some of the new "Coconut Chocolate Chip" flavor from them, on the theory they're so new and uber-tastee that the risk is probably low.

I've tried one other site from whom I've bought in the past, but they still haven't got back to me.
Ooooh! I just checked REI, and they have all three seasonal flavors listed, on sale for $0.99!

Does anyone know how long that price is good for?
Does anyone recall seeing the seasonal flavors in their stores, or are they probably web-only?
I'll be passing near one of their stores in the next two weeks, and will plan to pop in to try any they have.