[iamgabeaudick]

Lyle McDonald has a comprehensive two-part post on supplements (specifically for athletes, but applicable to all) on his blog, Body Recomposition. Here's part 1: http://www.bodyrecomposition.com/muscle-gain/supplements-par.... And part 2: http://www.bodyrecomposition.com/muscle-gain/supplements-par.... Lyle's a good bro.

Martin Berkhan, of Lean Gains, has also written on supplements, though geared more for bodybuilders. Here's the link: http://leangains.blogspot.com/2010/01/supplements-you-might-.... Both "gurus" are legit.