How do I speed up a site? [closed]

I've recently built a website that uses a lot of javascript and especially jquery but a few pages are very slow to load and I didn't know if there was anyway I could speed that up. I've tried loading the images first using a script I found here: http://bit.ly/HSDwcp but that didn't make any difference.
The page I'm having the biggest problem with is this one: http://bit.ly/yJDFfy although this page is also very slow: http://bit.ly/HQhrrF
I'd be really grateful if anybody could give any advice or pointers to help with this please. Thanks

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