Hey Bob, GNC is ***outrageous*** in price!!
It is possible to get many many supplements from www.beyond-a-century.com, they sell bulk powders of almost any supplement at super cheap prices. I highly recommend them, I have done buisiness with them for years.
If you don't want to mess with capping it yourself, I wouldn't buy from them. www.iherb.com is another great business, their prices are very low....and all their stuff is already encapsulated.
A great resource for what vitamins and supplements to take is www.lef.org, they have "treatment protocols" for many conditions. They also sell supplements, but their prices are pretty dang high too.
Hope this helps....
I just get what I need where I can find it. Getting sleepy requires 2 components when a woman is not near. I like herbal stuff for specific purposes. It works when needed. I remember the names of these things and ignore them unless I need them. Organic chemistry was a refernce point until I discovered physics. When doing this and math I need feeding:) Hopefully by a woman with a nice taste in burritos and tacos:)