Google, w3 total cache, it can combine and minify css and js as well as include proper expiration headers (for repeat visitors) and also can do page caching. This alone should help speed up your site.
However, for me your site loads pretty fast, upwards of around 2.5 seconds for total load time. Are you by chance outside the USA? Your server is in texas, and general network delay may be the cause for the "apparent" slowness. However, the real question is, where are your customers? If they're also not in the USA, then i'd recommend trying to get a host that is closer to where they are.