Actually man, try NO-Xplode. I am not a big fan of OTC supplements, but I was having serious problems with my workouts because I had ZERO energy and this stuff has been a real help to boost my energy levels up.
I agree with ortiz, no xplode works great. I have been using it for a few months now and have noticed better energy and intensity at the gym. I also like cellmass, made by the same company. I think GNC has it, I get mine at Vitamin World.
Used a ton of them the best to Date is Thremorexin, also when that isn't available I use a no Doze(200mg Caffeine) 2 mini thin (Ephra) 25mgs X2 =50mgs then in 20 mins i'm ready to roll!