You will notice, SD, that I've started exactly one thread about Machbusters, a build thread in which I explain exactly what I used to build mine.
What materials you need depends on what size motor you'll be using, your skill level, and the weight of the final rocket. However, there is no mid-power motor out there that requires advanced materials to build a Machbuster.
I'm going to ignore 18mm Machbusters here, because they're not worth the effort. Extreme weight requirements (< 20g), no payload ability, difficulty in tracking, yadda yadda yadda. Not worth your time.
For 24mm Machbusters, you have two options. You can go for the Aerotech F32T, which is a single-use motor. It'll allow you to use paper tubing and 1/8" balsa fins; or 3/32" basswood, so long as you make good fillets with wood glue. Or, you can choose to take the risk of losing an expensive casing, and use CTI Pro24 or Aerotech 24/120 casings. The longer casings will give you mid-to large G motors - eventually even a baby H from CTI - but they're expensive and require better building. If you want to use 24mm reloads, you could use ordinary paper tubing, but adding a layer of half-ounce fiberglass might be a good idea. Or get the the
Blackhawk 24 which is not cheap and is carbon fiber, but will survive any 24mm motor. Any.
You've also got two options for 29mm Machbusters. LOC tubing and 1/8" plywood fins will easily take up to a G80, and probably an H if you build it well. If you want to fly Is or you're on a hard desert, then fiberglassing or the Blackhawk 29 might be a better idea.
Also, consider this. Machbusters tend to go extremely high. A 29mm rocket on an G can easily hit 1 miles (5000+ feet), and a 24mm rocket on a G might go to 7000 feet or more. You will not be able to see the rocket at those altitudes, not even prolly with binoculars. You will need to put a lot of tracking powder in... baby powder, flour, and especially chaulk dust all work. You will see a little puff at ejection; launch on a windless day so that puff will be roughly above where it lands. Use a streamer that gives a descent rate of 20 to 25 fps.
For 29mm, consider dual deploy. It's a lot harder and requires a LEUP for the blackpowder, but it can easily increase the odd of ever seeing your rocket again by two or three times...