Analyzed Supplements+SNS can definitely get you what you need for your DIY fatburner. SNS has Raspberry Ketones, Caffeine, Yohimbine HCL, etc. and Analyzed Supplements has Forskolin, Alpha-Yohimbine (I forget how to spell it's actual form....starts with an R), etc. Some fat burners I'd actually suggest though that I find work best are:
PES Norcodrene
PES Alphamine
Antaeus Labs Lipomorph
BPS Combustion (trying it now and liking the results)