Katherine Kurtz is pretty much my favorite author, and it's definitely possible to get her books as ebooks.
The Deryni books are available, as are the Adept series (which she wrote with Deborah Turner Harris.)
A quick search for "Deryni" and "epub" (or Kindle) gets you plenty of places to buy them.
Also, FYI, if you go to deryni.org and look at the KK chat transcripts section of the forums, you can see that KK is doing alright. She's just busy writing, if the chat log is any indication.