Unico1242yahoo.com on "how to recover archives after being hacked"

I have been blogging for 3 1/2 years. Then someone hacked onto the blog and started posting as "author". The posts seemed spam-like in nature in that they seemed like key search engine words for pharmaceuticals and nike sneakers. I tried to get help from yahoo but that went no where. So then I went into the site and started changing all the "authors" who had been posting, to "Subscribers". The next day, when I opened the blog, all my posts and archives were GONE. There is a lot of material contained in the archives that has a lot of sentimental meaning for myself and others. I'm not horribly savy tech. wise but I'm not dense either so please advise.
http://www.luckycharmfarm.com/blog theme: Twenty Ten 1.2 by the WordPress team
Here is a list of my plug-ins to assist you:
Add to My Yahoo! Button
After The Deadline
Akismet
Customizable Permalinks
Hosted by Yahoo! Badge
WordPress Database Backup
Yahoo! Blog Statistics
Yahoo! Search Box
These are on my Dashboard but not activated:
FAlbum
Subscribe2
wp-cache