I also use the "water in tub" method in my unheated basement. Using ice bottles, it's easy to regulate temps in the summer. In the winter, I use a adjustable 100W aquarium water heater. The water heater is very useful to bump up the temp for belgians and for a lager's diacetyl rest.
I also add a touch of star san to the water if it is going to be in use for more than a week.
I recently posted something that you might find helpful. In summary I found that trying to control fermentation temperature (especially ales) is very difficult if you are using glass or plastic fermenter - say you want to ferment at 68F so you put your fridge at 68F - problem is some ales will drive the fermenter temperature up as much as +6F. Due to the laws of heat transfer, it is much better to place the glass or plastic fermenter in a temp controlled water bath. The fermentation will always be within 1 degF of the temp of the water. Here is the link.
I have my 2nd beer in my swamp cooler and for the second time I have a batch that hasn't been above 68 even with heat of fermentation. Wyeast 1028 had no trouble bubbling away at 68 nor did 1968. I'm really excited to taste these in a few weeks, they not only represent my first under 70F fermentations but also my first two 'full boil' batches. Needless to say I have high hopes
Thanks for that tidbit, I'm going through my first winter of brewing and my basement floor will get that cold in the next few months, the 'book' method sounds great!
The spot near my basement door is usually around 60-62F from Nov-Mar. A towel on the floor under the carboy serves as a suitable barrier to achieve my 65-66 temp target. A little tougher in July when the temps are 100F outside. I've gotten use to drinking lagers in the winter and ales and stouts in the summer.