The Mythos of Santa (and having to decide to believe or not)

Santa never came to our house when we were little.
It's not because I was a misbehaving kid, or being punished for pulling my sister's arm out of the socket when she was a little over one.

I don't think the idea of Santa was wide-spread in Japan yet (he was a mascot character for winter events, but not someone who actually gave you gifts), and I checked w/ Ichigo and she confirmed that we never got presents from Santa.

So I never believed in Santa.
And the concept of Santa is foreign to me.

It never hampered my life as an average citizen... until now.

When you have kids, all of a sudden you're forced to decide...Do we believe in Santa or not?

Okay, some people don't need to decide. It's a given. Santa exists for kids, and you keep the idea going until they start questioning it, no longer believe or something.

But for me, I have to learn this Santa business.

How do kids find out about Santa?
What age do you start talking about Santa? How do you make him believable? What's his back story!?

F*ck.
I don't have memories of the Santa fantasy (or the disappointment of finding out the truth), so it's really hard to comprehend.

I didn't know Santa gives you the gift you most want (or the expensive toy).
Man, you get the gift your kid wants the most, and you don't get credit for it? That kinda sucks. (Yeah, yeah. The joy in your kid's face is rewarding enough. Bah!)

So is that the joy of Santa? He knows the gift you want most? And you try to stay out of trouble, listen to your parents, don't pull your sister's arm out of the socket...so he'll bring you your favorite-ist toy ever?

What is magical about Santa?
He comes in the middle of the night to drop off gifts? Hmm. How do you know Santa dropped off a gift when there are other gifts under the tree? Doesn't it get lost in the pile? Or is the box so big, it's hard to miss?

And I knew about leaving cookies & milk (TV commercials tell you so), but I assumed you just buy cookies. Our friends are posting on FB about baking cookies w/ their kids. What!? Do you know how much mess I make when I bake cookies? The thought of baking w/ a 3-4 year old is making me dizzy.

I'm sure it's cute when kids believe in Santa.
But the cynical part of me would be twitching at the face if I had to play along with the Santa mythos.

Which brings me to the really important part.
I don't want to be the adult, nor do I want to have the kid, that ruins the Santa fantasy for other kids.

I've already come pretty close.
I openly talked about "not doing Santa as a kid" in Popo's music class. There are kids 2-4 years old who fully understand what adults are talking about, and some of the parents looked uncomfortable. I only realized later on that the parents were nervous their kids heard me.

Ugh.
If I'm not making any friends in the parent/tot classes, this is why.

So we haven't decided whether or not we'll believe in Santa yet. Popo is still scared of people in costume (Santa included), so we haven't even tried introducing her to Santa. I think she might know what he looks like from cards, books, TV and iPad apps, but not sure what he is.

But we'll definitely need to decide by next year, since she'll understand more and some of her friends will believe.

Is there a good book to read, so it'll help a first-generation Santa-ican understand this childhood magic?