BMX - Help a noob?

I've been mountain biking for a while, and I have been thinking about getting into BMXing. Only problem is, I don't know where to start. First of all, I'm a pretty big guy (15 and 5' 10", on the heavier side), so I'm not sure if I should get a 20" bike...do they make bigger BMX's? Also, what is a good beginner bike for a low price range? All help is appreciated.

How much on the bigger side are you? What's your price range? What will you be riding?

for the best bang for your buck you could always try finding something second-hand. there's no shortage of people who bought a high-end bmx thinking they'd get right into it, rode it for a season and then got bored and stuck it in the garage for a few years. if you shop around and do your research you can probably score a quality ride in almost-new condition for half the price it would've been new. particularly if it's your first bmx and you don't know if you're gonna stick with it long enough to justify a big investment.

I'm not sure if I should get a 20" bike...do they make bigger BMX's?

They make 24 inch cruiser bikes. Being about 5'10" myself I considered one for a while. I finally bought a 20 inch and I am glad I did it since all I use it for is playing around, but I also have several other bikes for different purposes. If you are really buying a bike for tricks and jumps then absolutely get a 20 inch. If you need a more versatile bike consider a 24 inch.

20 inch bmx bikes frames come in different sizes anywhere between 20 inchs and 22 inches. i wouldnt recomend a 22 inch for anyone not over 6 foot 2. im 5'9 and i ride a 20.2 which is short but im planning on getting a 20.6 when the frame i want comes back in stock. i have also ridden a 21 inch long frame and it was too long in my opinion so i would suggest anything over 20.5. i keep tellin everyone to go to there local bike store and tell them what you are lookin for how talll you are and they should help you out.

Well, I'm 5' 10" and around 200 pounds, so I didn't know if the wheels and stuff would hold up, but I guess they would hold the same at bigger sizes, so I don't know. My price range is pretty low, like borderline broke I guess, but either way what is a good brand and where are some places I should look for secondhand?

I would look into a used bike. Sometimes you can find a good deal on a good bike. But, if not look into DK, Haro, Kink, etc.

Haro's are good bikes? If so, I've found a good deal on them.

Yeah depends on what kind.