I think your site looks great! The beauty and simplicity of it is wonderful. I think the heart and rollover effects are awesome.
I looked at your source code and tweaked around a bit and saw that you may be able to center it by adding the following code just below the opening body tag:
<div style="width:955px; height:600px; position:absolute; top:50%; left:50%; margin-top:-230px; margin-left:-400px;">
I got it centered pretty well but I was unsure of how far from the top it should be. You may need to tweak the numbers a bit more.
To get it farther to the right, change the margin-left value from -400 to -390 for example.
To move it to the left, change the margin-left value from -400 to -405 or whatever value is needed.
For getting it farther away from the top or closer to the top, just play around with the margin-top value. Leave the rest of the code the same.
Let me know if it works.
~Missy