fix speed of the site

We have a website that is way too slow. We have a problem with slow server response on our pages, We have to wait up to 10 seconds for the pages to start to load. We us Joomla for the site, and virtuemart. Apparently, our first page contains many script tags at the top of the file. Whenever a script is called, the browser stops everything else until the script is loaded, and then continues. As there are multiple scripts in a row, the browser has to run all of these before it can continue loading the page. I would recommend placing these scripts near the end of the file. We need this problem solved.