So far today it seems that there are no new problems, although I am still scouring the hundreds of pages of musings to find anymore nefarious edits and additions. 

I did manage to test my theory of how this vandalism was performed though. Using my netbook under a guest account, I managed to break into my own WiFi network, get my password protections removed (and restored later) and retroactively added an extra page to one of my blogs. So at least now I know how it could have been done.
But with any luck, the problem is now resolved and I can finally get back to my real work. I can't believe how many hours I have been forced to waste undoing damage from someone seeking to perform random acts of cyber-vandalism!

UPDATE: It was a false hope after all. I discovered another edited page, again done by some hacker. Why did they select me? 

In any case, I think I have it mostly fixed now, but as usual if someone spots something awry then please let me know. I know I can never completely repair my website, but I hope that with time and aid that it may get back to a reasonable facsimile of what it once was.

UPDATE: I should also clarify that I don't mind if friends, family and even co-workers have been reading my private blog. Although it wasn't meant to be public, I really don't mind if people did read it. Just remember that I didn't write some of the pages.