How do you permanently delete web browsing history from your os x system?

I am using OS X 10.5.4 on a MacBook. I'm new to owning a Mac and previously had a Windows notebook where everything was easy and technical. I like to clean up my computer after every session and want to know how to permanently remove web browsing history from the system.

I know how to remove it from Safari, but it still shows up in Spotlight searches and I'm pretty sure it's still hanging around on my computer somewhere.

I'm pretty much Mac-illiterate so you're gonna have to break it down for me.

PM or email me please.

Thanks

You can also turn on Private Browsing, which doesn't save any of your history. You can also manually delete all the cookies and stored files in Safari and Firefox.

Delete your bookmarks as Safari will use them to auto fill addresses
Clear History > Tool bar > History > Clear History at the bottom.
Delete Cookies > Safari prefs > Security
Delete Cache > Under Safari
Reset Safari > Under Safari