Amazon.com is a good place for shopping around, believe it or not. I found Panaracer 27x1 TG for about 20 bux there a few weeks ago. They are a channel for Niagara Cycle Works, BTW (but that's not where I got the TGs for 20 bux).
For 1"/25mm tires, I recommend you get smaller than 1-1/4"/28mm tubes. The larger tube will tend to get pinched between the tire and the rim as you assemble, making the process very finicky, and potentially blowing out the tube if you inflate with the tube pinched because you didn't see it.