You should buy boots first, and don't have any preconceptions going in, don't bother researching. Just try on every boot you can find, and get the most comfortable. As tight as possible without being uncomfortable a bit tight is alright (but not painful) they'll break in. Loose isn't...they'll break in, and then your ankles. I say don't research because if you're anything like me, you'll get your heart set on something, then find yourself reasons to buy it. That's alright for bindings and boards, not boots.
After that you can check out bindings: try renting Flows before buying, I've never tried em but they inspire a strong love/hate. Rome and Union are two well-loved brands for traditional bindings. Then go for boards, there's a crapload of companies that offer quality boards. If you're looking to go cheap most of them offer cheaper beginner boards. Since you're interested in Flows, I'd suggest renting decent equipment (As opposed to the cheapo-rentalshop crap) two days, one with Flows and one with regular bindings and two different beginner level boards that catch your eye to get a feel for what you want.
But honestly, if you can find stuff (Bindings and boards) dirt cheap and they seem good enough, go for it. I got my whole first set up for $100 off Craigslist. You can use it to figure out what you're really looking for, and if you really like snowboarding then upgrade next year without feeling bad.