Hello Skyeone, good to see you came over
As has been said, check out the for sale section one here. Like i said on Vital though, at your height you really don't want anything with a Top Tube over 19" & Chain Stays over 13" ... I know a few people have said don't worry about what you ride etc.. But i know you really want a Flat Specific Bike so check out the For Sale Section.. If you can pick up Parts something along the lines of these it will help you get your "Flat" Bike.
Frame: 18.5" to 19" Top Tube, Chain Stays under 13"
Fork: Zero Offset with at least Removable Mounts (Having at least a Front Brake WILL help when learning)
Stem: Nothing over 36mm TBH, you want something Short & Tight!
Bars: 8.25" to 9" Upsweep is great 3 to 6 depending on the Bars, No more than 6 Backsweep
Seat Post: 300mm + So you have lots of Post to get the perfect Seat Height!
Sprocket: I wouldn't go more than 23t, you want nice light gearing!
Cranks: Don't worry about Ti Spindles & all that, Just get yourself something with Crank Arms no longer than 165mm! 155-160mm is most peoples preference.
Tyres: Lots of people prefer very narrow Tyres, it helps with rolling switches faster. I myself really cannot get on with anything under 1.85"! Look for something 1.85" to 2.0"
Freecoaster: I think along with Pegs, a Freecoaster Rear Hub is really the most important thing you can get for your Flatland Bike.. I don't know how much you know about them? But it allows you to roll backwards without your Cranks engaging & spinning backwards, so you can spin & roll in all directions without your Cranks moving unless you pedal!
Pegs: Quest BMX MetaGuruStix
But yeah, you want something 4.5" Long & i personally do not get along with super small O.D Pegs 1.475/1.5" Doesn't cut it for me, KILLS your feet. BUT 1.75" are rather Large! However they are GREAT on your Feet! Quest BMX MetaGuruStix offer a 1.625" O.D Kinda in between best of both worlds kinda deal! Knurled Pegs ARE better than Grip Taped Pegs.
Other than the Parts i have mentioned that are "Flat Specific" I guess :S , you could run pretty much whatever you want! Hope that helps Buddy.
Welcome to Global Flat.