Logo Images Missing and CSS Errors on Internet Explorer

I have been working on a web site at libertyfa.org, which has been going well except for some Internet Explorer compatibility issues.

When viewing the site on IE, the logos (left on menu bar and bottom center) disappear and are replaced with my theme’s default image. Also, the front slider nav arrows are a bit off. Any help on sorting this out would be greatly appreciated, I understand it should be a css-fix; however could use some guidance as to where I should start.