Congratulations, HHF! Welcome to the wonderful world of dog ownership!
I have 2 lab mixes, which are a little different from the Shiba Inu in that they probably need more exercise, and are also a little less temperamental. The Shiba Inu is a great dog, though; my neighbour has one, and I dated a girl in University whose mom had one too. Very pretty coat, elegant stance, etc.
Some stuff to watch out for: In my experience, which is pretty limited (2 or 3 examples) Shiba Inu tend, like other small dogs, to bond with a smaller peer group and be a little distrustful of strangers. You should find out whether the dog (who is 4, right?) has been socialized to be around children and other dogs, because the Shiba CAN be aggressive. I'd suggest either taking a canine obedience class with your new dog, or at least getting a book about it. They can also be a little dominant--it's kind of a famously bossy breed, sort of like Weimaraners, and so you need to establish a pecking order and stick to it, which means little things like making sure that you always have first priority on beds, couches, etc. and that you control traffic. I'd also, VERY CAREFULLY test the dog for food aggression by petting him/her while they're eating, and if that goes well, removing the bowl and giving it back, putting your hands in the food, etc. Food aggression isn't the end of the world, but if your dog is food aggressive, it's important information to have.
If you do obedience, I recommend clicker-training as a method rather than choke collars--it's worked wonders with my dogs, who amaze our friends at parties with their tricks, and are also pretty well behaved.
It's an exciting journey to embark on, IMO! A dog is like the most loyal, affectionate best friend you could ever have--they never judge you, and they really don't talk much.
Let us know how it goes!