H.Q.
First, for the digital camera for your girl - Wal-Mart and K-Mart usually have some in the $20 area. We got one for my daughter - it was Little Mermaid. Ate batteries like mad, tho - so if you get one of those, make sure the batteries are out when not in use.
As for amount we spend - well, I don't really keep track. I buy equal numbers. But, I think $135 is totally reasonable for the kids.
As for the saving part - check with your bank. I know that if you have an account at a credit union, they can set up a "Christmas Club" account for you. You specify a dollar amount to be put into this account each month and in October, it rolls over into your (I think) checking account. It's pretty simple - we did it a few years. I don't know if banks offer anything like that - but you might want to check.
Christmas is hard. And that sucks - my folks made it look SO easy!! No wonder they didn't want to get up at 4 o'clock on Christmas morning!!