What do I do if I lost my restore DVDs and have a corrupted HD in my Macbook Pro 2010?
There is no Lion DVD on sale, however, Apple sells Lion USB Key, that you can use to reinstall Lion on a new hard drive.

What you won't have, though, is iPhoto, iWeb, iDVD (I probably forgot some) that come when you buy a Mac.

But if you bought them on the Mac App Store, you'll be able to reinstall them at no charge.