well then METH is the way to go cheap, easy to get, you can make it yourself, and it will last all day... Right on brotha.... Hit that meth pipe!!
This is my advice. [from experience] Meth is NOT a recreational drug. Meth is a tool. Do not enjoy meth, most people don't. Have a valium handy, and buy in small quantities, deposit all of your cash, use after the banks close, and put your bank/credit cards through the blender. Smoke it and you're a dummy. Take a rail, .25 should last you a whole day, and then take that valium when the meth is gone. Use it to do work, don't use it to prolong a night of drinking, etc.
The best recommendation is
get good sleep eat right and exercise. If your life requires you to be superhuman, maybe you need to change some shit in your life.
Though you seem pretty set on the use of some uppers, so if you're gonna do it, do meth... You're gonna end up there anyways.