B Complex and calcium supps taken just before bed can help with sleep, especially if that is a need your body has. If you have variations in genes that determine your efficiency with absorption and utilization of these, you need more than the standard dosage and may need it in a form that is more absorbable than what is available on the shelves of your local store.
Don't buy supplements that are so cheap the cost of the supplement is what the company probably spent on the bottle, label, and labor! I get these catalogs all the time, as a massage therapist....it goes something like this: Only $5 for a month's supply! Or buy 6 for only $10! Buy a case of 12 for only $15!
Those scare me. Of course, I am a bit scared of contamination, especially from things sourced from countries far away with even less regulation than we have here.