tnsmart

Thanks for the response.

After a lot of trial and error, I was able to center my menubar.
I imagine the changes are similar for the other themes, but for the Superfish theme, lines 133-142 of ssf-blue.css originally look like this:

position:		relative;
	z-index:		49;
}

/*** DEMO SKIN ***/
.ssf-blue {
	float:			left;
	width:			100%;
}
.ssf-blue a {

but to center the menubar, should be made to look like:

position:		relative;
	z-index:		49;
	text-align:		center;
}

/*** DEMO SKIN ***/
.ssf-blue {
	display: inline-block;
}
.ssf-blue li:first-child {
	border-left:	1px solid #8EC3F7;	/* border color */
}
.ssf-blue a {

The last few added lines are to enable a left border on only the first menu option.