PINGDOM and IWEBTOOL are two useful web resources to check your blog/website load time. Load speed is also something that Google is now factoring into ranking. So if you want to do well in the SEs you better load fast into browsers.
Check out these links to know your site's/blog's loading time -
Among PINGDOM and IWEBTOT, PINGDOM is my favorite for simple reason , I can see which script is taking the maximum time to load.