Hi Connor. Welcome to the MEPD. Yes, you have come to the right place. To get started here, check out this section:
And check out the CRL (costume reference library):
And check out this thread for help in selecting a kit:
This hobby is really about the research. Take your time, do some reading, and ask questions. There a number of options for buying armour - all depends on your budget and body size. The do-it-yourself kits are very rewarding and will save you a few bucks. Try to stick with vetted sellers - and remember, if a deal looks too good to be true... well, you know.
Also, since the sandtrooper armour is almost the same as an A New Hope stormtrooper, you might want to also check out FISD (www.whitearmor.net) for additional information and general tips for building armour. Of course, once you get into the sandtrooper details such as backpacks, pouches, and BFGs - nothing beats MEPD.
Good luck with your journey!