Dave, you can scoff all you like, (and post as many laughing smileys as you like), but in 1969 people were only able to follow the rocket on telescope as far as the ionosphere. Above that you could not track it due to the Earth's rotation and the (rather convenient) radio silence and blackout.
That's not quite accurate, F; the big telescopes around the world were able to track the approach to the moon (although the question is one of resolution: how big does an object have to be before a telescope can resolve it, that is, see it as more than just a dot? As an example, a person standing next to you is easy to see and easily identifiable. But from a mile away that human is far more difficult to see, and from ten miles away is just a dot, if that. The ability of a telescope to resolve an object is, as you’d expect, directly related to the size of the mirror or lens. There is a simple relationship between mirror size and resolving power: R = 11.6 / D, where R = the angular size of the object in arcseconds. An arcsecond is a measure of angular size - how big an object appears to be: if two objects are the same physical size, the one farther away will appear smaller, and have a smaller angular size. There are 3600 arcseconds to a degree, and to give you an idea of how small a measure this is, the Moon is about 0.5 degrees = 1800 arcseconds across. D is the diameter of the mirror in centimeters. Hubble’s mirror is 2.4 meters = 240 centimeters across. Plugging that into the formula, we see that Hubble’s resolution is 11.6 / 240 = 0.05 arcseconds. That’s an incredibly small size; a human would have to be nearly 8000 kilometers (4900 miles) away to be 0.05 arcseconds in size,), and the radio silence you mention was only induced by the plasma generation during the few minutes of re-entry. Additionally, since the late 2000s, high-definition photos taken by the LROC spacecraft of the Apollo landing sites have captured the lander modules and the tracks left by the astronauts. In 2012, images were released showing the Apollo flags still standing on the Moon.
Some have argued that one of the main motives of conspiracists is making money from pseudoscience. In November 2002, actor Tom Hanks, who starred in the movie Apollo 13 and produced the documentary From the Earth to the Moon, was asked what he thought of the conspiracy theories. He replied: "We live in a society where there is no law [against] making money in the promulgation of ignorance or, in some cases, stupidity".
It can also be argued that the conspiracy theories are impossible because of their size and complexity. More than 400,000 people worked on the Apollo project for nearly ten years, a dozen men who walked on the Moon returned to Earth to recount their experiences, plus 6 others who flew with them as Command Module Pilots as direct witnesses, and another 9 astronauts who orbited the moon (which proves, at least, that the Saturn-V was capable of reaching the moon, a feat which some hoax theorists claim wasn't possible.) Hundreds of thousands of people—including astronauts, scientists, engineers, technicians, and skilled laborers—would have had to keep the secret. It can thus be argued that it would have been much easier to really land on the Moon than to generate such a huge conspiracy to fake the landings, Finally, the placing of the highly directional laser reflector units, which allows us to bounce relatively low powered lasers onto the moon and time their return to Earth (as demonstrated on the Big Bang Theory) suggests that either an alien race trying to be helpful placed them there or we actually landed on the moon.
However, the veritable Tsunami of evidence supporting the moon theories apparently means little to the deniers (who, curiously, are often the first to suggest that aliens visit us on a regular basis) so I'll leave the last word to Discover magazine:
"Once you stick your fingers in your ears and start saying "LALALALALA I can’t hear you" all bets are off, and no amount of evidence will help. The only thing to do is to go back.
And that’s just what we’re doing. Not to prove to Apollo deniers anything, of course. They can sit here back on Earth and pretend it’s flat if they want. But the rest of us will look up, look out… and shoot the Moon."