Target has their AirWick Freshmatic Starter Kits on sale this week (until 8/15) for $5.99. There was a coupon in the 8/9 Sunday inserts for $6.00 off AirWick Freshmatic, making them FREE!
Now, if you don't have a Target, but do have a Walmart, you should still be able to get them for free. Just take the Target ad to Walmart, and they SHOULD price match the Target ad for you. I say "should" because I've read where people have problems with their Walmart taking coupons, price matching, etc. I have a Target about 20 minutes away, but I have a Walmart 5 minutes away, so I took my ad and coupon to Walmart and got them free.