iWeb has not been discontinued by Apple, that is MobileMe, so please note the difference. iWeb is an app and you can still use it.
Yes, if you want iWeb you will still need to purchase the boxed set of iLife 11 that contains iWeb and iDVD and you can purcahse this from the Apple Store online or from Amazon.
There is lots of other web design software available for the Mac - just search this forum by putting in something like 'alternatives to iWeb' and lots of topics will come up.
Your unique question is asked on an almost daily basis on these forums!
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