Well, good for you Adam. There's nothing quite so frustrating as an unruly, destructive puppy! Honestly, I came home the other night and found my coffee table book - a beautiful hardcover of 100 years of New York photography, that my fiance gave me for my 30th birthday, in bits on the floor.
Now, my dogs have walked past that darn book every day of their lives and never looked at it once!
When I got home and found it all I could think of was murder and revenge!
. What I DID was calmly put the dogs outside until I had cleaned up the mess, and let them back in and pretended it never happened.
They weren't being naughty, they were being dogs. If I didn't want my book chewed, I shouldn't have left it there - even though it had been there for months without a whiff of interest.
Older dogs are much easier to teach boundaries to. Puppies will be puppies, and you just have to wing it and teach them their basic manners, obedience and commands.
As my vet says, they will `grow a brain' at around 18 months, and then you can start relying on them a little more.
Get `The Dog Listener' by Jan Fennell - you said you are still learning, well, it's the most valuable learning tool I have ever, ever read, and in my work as a trainer I implement it's principals all the time.
You were raised under the `spanking' method as you say - well, this book will help you understand why that doesn't work with dogs. You don't do it, clearly, but I get the feeling that deep down you don't really understand why it wouldn't work. This book is will explain that in a way so you go, `Ahhh NOW I see' - it's amazing, and I can't recommend it highly enough.
Good luck with your pup, you're doing a good job.