I had great results with alpha lipoic acid combined with acetyl-l-carnitine, a combo researchers at UCLA reported "made aged lab rats do the macarena." I felt wonderful, looked glowy, and my fingernails grew in without the horrid grooves they'd developed. Other amino acids are effective too.
For really cheap supplements, try http://www.beyond-a-century.com
This company was recommended by another freeper and I've been buying from them for years. My favorite exotic is GABA, gamma amino butyric acid, reported to have made aged lab rats smarter. I tried it. It absolutely does wonders, restoring some connection between brain and eye that breaks down as you age. This one made a major difference for me. As in MAJOR. $5.50 for a five-month supply at Beyond A Century.
BTW: According to my reading, only four mammals in the world are incapable of making their own vitamin C. fruit bats, gorillas, humans, and I can't recall the last one. But all the others live in areas where their diets are high in C. Humans being omnivores, don't get nearly enough and the FDA's MDR (60mg) is only enough to stave off scruvy.