I believe that one of the pages of the site that I'm creating is shifted slihtly to the left. I may be going crazy, but I'm pretty sure that's what's happening. The page that I believe is shifted is: http://armyants.us/members.php?steam=All If you guys could help me out here, then that's be pretty awesome. Thank you for your time!

Looks fine to me (Chrome on Mac). Have you thought it may just be the scrollbar making it appear this way?

It looks fine, what browser did you preview this on?

The only differences I see are these:
Your border-left and border-top are 1px wide on this page. On other pages they are 2px.
On other pages you have padding: 0 10px 10px; for the main content div. On this one there is no padding. That may make it look like your content inside the div has shifted left, because it's not being pushed as far from the border.
Keep in mind that if you do add padding and border width, you need to remove it from the width so the overall size of the container is still the same:
Current overall width: 1001px -> (width: 1000px, border-left: 1px)
If you add padding: 0 10px 10px, this will add 10px on the left and right, so:
1000px - 10px [padding-left] - 10px [padding-right] - 1px [for changing border-left to 2px] = 979px [your new width]

On a side note, you have <link> and <script> tags in the body of your HTML. These should be inside the <head>, not <body>. The script could go in body, but there's probably no need for it to be in this case.