Here are a couple that I have made:
This was Griffin's First Birthday. The monkey on the bottom of the left page is a stamped image that I colored with markers. (The Monkey was inspired by his favorite thing at the time, his monkey binkey a/k/a Nippy.) The accent pieces all came from a free pack of Creative Memories paper that was given as a goody bag item at a crop I went to.
For this layout from Owen's 7th birthday, I cut the 1" squares from photos of the gift bags.
Here is a link a blog from Tami Potter about other inspiring birthday layout ideas: Six Ways to Make your Birthday Pages Sing