Ebay
For a mere $65 per bottle ($1.30 per pill) you can find out. At $1.30 per tankful, this is the equivalent of 9 cents per gallon of gas, or at the current price, you need about 7% better mileage just to break even.
For a mere $20 you can get a little booklet about how you can join in the multi-level marketing scheme to sell and distribute these things.
One thing that kind of concerns me, frankly, is that in the MSDS it gives the specific gravity as being 1.14. That basically means that this stuff is much much more dense than gasoline (spgr about .78), and probably consists mainly of a mineral filler (dirt) of some kind which has a really excellent chance to plug up your fuel filter. Also note that this stuff originates in Mexico, out of reach of the normal US legal system, etc.
Note that I am not saying this won't work. However, we learned from the famous Acetone experiment (in the "conservation and efficiency" forum) that if tested carefully (several tankfuls of gas compared to several tankfuls of the "doped" gas) and you run the statistics, you have to have a pretty big difference to be significant, because there is quite a bit of variability due to different sources of gas, different driving conditions etc. and unless you are really meticulous about keeping track of your gas usage, you cannot really make these glowing success statements on the basis of a couple of tankfuls. That, combined with the fact that you need 7% or so to break even economically makes the whole thing kind of dubious.
However, I am willing to be a good sport and try it, so I offer the following proposition: If 10 people volunteer to deposit $6.50 each in my paypal account, I will buy a bottle of this stuff, and send each of you 5 pills each (I will be a good sport and pay for the postage myself). You then should test the pills in the following way: Run five tankfuls of normal gas, and keep track of the mileage. Then, run five tankfuls of "doped" gas, and keep track of the mileage. Then, report the results in this thread and we will do statistical analysis (t-test) to determine whether the difference is significant or not, so we can see whether or not the pills "worked", like we did for the acetone. Important note: the experiment should be completed before the first week in May, because that is the time that "summer" gas is marketed in select markets. Therefore the participants should probably be people who burn about a tankful per week. Also, the ideal candidate should be some commute-a-holic that drives pretty much the same route under the same conditions every day, and does not let the rest of the family drive their car.
Also note: I figure we should assign about half the group to use the pills first, then do the control and vice versa. Reason: if you run the pills five weeks from now, it is likely that the weather will be warmer and this might make the mileage different. So some people should run the pills first, and then some others should run the pills last.
The participants should also note whether or not they need to do any unusual maintenance i.e. replace the fuel filter when it plugs up with dirt.
Anyway, that is the proposition. Report in below if you are willing to run the test and if we can get ten volunteers, I will coordinate this, as a public service, exclusive to PO.com posters!