Lion no longer includes iDVD, but you can purchase the retail iLife 11 disk at various online sellers such as Amazon, eBay, and others. I bought it to make sure I can reinstall if needed since there is no equivalent for iDVD with its customizable menus and themes and I use it extensively.
There is also Roxio Toast ($$) or others, some free and none that are as versatile as iDVD.
got several called
can't remember if they were all from the app store though but I didn't pay for any of them nor are they pirate software of cause
or a google like this should also provide a wide variety of solutions
https://www.google.dk/search?source=ig&hl=da&rlz=1G1TSEH_ENDK367&q=dvd+authoring +mac+&oq=dvd+auther&aq=3l&aqi=g-l10&aql=&gs_l=igoogle.3.3.0i13l10.1333533.133550 8.0.13384184.108.40.206.0.0.0.108.712.6j2.8.0...0.0.D97sMvR-OqY
I've just bought an iMac OS X Lion 10.7.4 (11E53) but there is NO iDVD on it.
If you are still within your 15 day return period. Call Apple they will sent out iDVD at no charge. (There are NO realistic substitutes.)
Nicely explain that you may return the computer without iDVD. That usually does the trick. You MUST speak to a senior advisor to get a free copy. The first tier people cannot do it.
If that doesn't work you can purchase iLife 11 (includes iDVD) on disk.
IDVD is a wonderful piece of software and well worth the low cost of $40. ( NOTHING else comes close.)