Been wondering if lockdown mode really works... I hope to find out someday, but my WP blogs are quite niche and not prone to being dugg.
Anyway... I have lunarpages for some personal stuff and let friends host little webpages there and make them FTP accounts.
All in all, Lunarpages sucks from a technical standpoint (downtime and such), but their support is friendly and they're cheap. I like having some personal domains on a different IP from my biz IPs.
The solution here is easy. You should have had wp-backup e-mailing you database backups to a separate spot (I have a google apps account where I get my backups sent to), and you should have a backup of all your html/php files. Restore everything elsewhere and re-point IP.
If you have that much traffic, you can afford VPS and someone to support it.