First off, congratulations on creating your first product! Feels awesome does it not?
Overall the site looks you are off to a good start, but of course its marketing so you can always be tweaking something.
I would start off by tweaking the size of text, its MUCH too small. Look at this page in a Macbook, if you can't read it there, then size it up.
Someone in this thread mentioned that there is too much text, i disagree, long copy sells. Just if you get long beyond a certain point make sure to have two readership paths, ones for anal people who read everything and then a path for skimmers.
The benefits of the product can't be stated clearly enough. You need to get it out there that this is "energy and focus without the jitters." Flesh it out.
With bigger front and more text, don't be afraid to put the checkout button 3 or more times on the same page.
Get a copy of one of the "replay" analytics tools tapefailure, clicktale, robotreplay etc... See how real visitors interact with your site. I am working on a FOSS tool called Freetale, but its going to a month or more before its ready.
I also agree that having a continutity program is _essential_ to your products success, let me tell you, many people do want there glop comming in every month. I would make the pain page have a optin to continutity at checkout (giving a great discount). At any rate make sure you are following up with your (e)mailing list to remind them if there supply is likely getting low. Of course give them the option to get two or more bottles a month if need be.
Feel absolutly free to make a seprate landing page for a continuity only on a seprate domain. energysupplementreviews.faux which gives special "never before seen" discounts for "getting plugged into your bodies natural potential for focus and energy."
Get affiliates and train them AND get them to send out email blasts in unison. Give your affiliates email templates to send out when you need a nice quick boost in income. Its an effective way to build buzz. Give your emails value, by adding at least these three ingrediants.
1) A quick and easy way to be more healthy about 3 sentences.
2) A _narative_ of someone (real person) who is using your product and has had a positive results
3) Some Call to action (including having them FWD this email to friendS (plural).
Start thinking about how you are going to make this suppliment part of a corriculum of products, ASK your list what other problems they have (not getting quality sleep, too stressed out, not enough stamina, etc...) Then build products to solve those products. Make the products in levels, silver, gold, platinum versions of the products or subscriptions. Silver members get the product, plus a ebook, gold also get online videos and discounts, platinum also get a DVD- direct emails with nutrition expert, etc...
Good Luck!