Books:

• The Priceless Gift by Cornelius Hirschberg (OP)
• How to Read a Book by Mortimer Adler and Charles Van Doren
• The Well-Educated Mind: A Guide to the Classical Education You Never Had by Susan Wise Bauer
  • Well-Educated Mind Website
• The New Lifetime Reading Plan by Clifton Fadiman and John S. Major
• Invitation to the Classics edited by Louise Cowan and Os Guinness

Articles on the Internet:

• "Educating Ourselves" - article by Susan Wise Bauer (co-author with Jessie Wise of The Well-Trained Mind)
• "Suggestions for Educating Yourself (It's Never Too Late)" from Schola Classical Tutorials

Other Internet Resources:

• Classical Self-Education Page
• The Teaching Company - "Enjoy the best of lifelong learning everyday. America's college-level stars teach courses specifically performed for lifelong learners"
• Blackstone Audiobooks - "Unabridged recordings that Inspire, Educate, Entertain"
• Studying Latin as an Adult - Tips
• Introduction to Repairing the Ruins (book by Douglas Wilson, introduction by Martin Detweiler)
• Articles at Veritas Press

General Advice:

• One place to start is by reading books in which you are really interested.  Have you always wanted to read Pride and Prejudice?  Begin there.  Did you see an interesting show about Ernest Shackleton?  Read Endurance by Alfred Lansing.  It's much easier to get started when you are excited about the book.  Then you are motivated, and you can't wait to find even five minutes to read it.  After a few of those books, you will have established a habit of reading and acquired a little background knowledge and reading skill to help you in your future reading.
• Another starting place is to read the unabridged versions of the books your children are reading.
• Hirschberg (above) recommends beginning with history.  History is a wonderful place to start, and continue with, and read more of...
• I found this quote in the Veritas Press catalog:

"The man who doesn't read good books has no advantage over the man who can't read them." - Publilius Syrus

So what are you waiting for?  :-)