Why exactly do you want it to be JSP? Any particular reason?
Do you want the site to be dynamic with a 'Content Management System' or a 'Shopping cart'? Like JhonCena mentioned, PHP is much popular and widely accepted language.
Tryout these tutorials for JSP, on these websites:
*www.jsptut.com/
From Sun Developers Network:
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*java.sun.com/products/jsp/docs.html
*java.sun.com/developer/technicalArticles/Programming/jsp/
I prefer 'notebook' for my coding. If you are looking for a good web builder, try out the trial of Adobe Dreamweaver 8. There are many free editors like Notepad++4.0.1. And Eclipse might be a good choice since you want an editor for jsp.
Notepad++4.0.1
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*www.download.com/Notepad-/3000-2352_4-10637422.html
To Incorporate flash you would need to develop/design the flash components separately. I recommend you to tryout Adobe Flash 8. You can download the trial versions from Adobe. It is the best, but a costly software to develop flash elements. Anyone who can suggest freewares?