We used a pinwheel theme for our son's first birthday. He doesn't have any favorite cartoons or characters right now so we didn't want to do a character theme party at this point.
I checked a lot of ideas on Project Nursery, Etsy, and Pinterest. I based my color scheme off of the birthday hat & bib I ordered from Etsy.
The birthday hat & bib were the color inspiration. I ordered them from Dainty Couture on Etsy: http://www.etsy.com/shop/DaintyCouture
The invite template I also ordered on Etsy from Announcing You: http://www.etsy.com/shop/announcingyou I used that template to print the invites on Vistaprint.
I made all the pinwheels with scrapbook paper from Michael's.
I also made the happy birthday banner with free banner templates at http://www.shanty-2-chic.com/2012/10/free-printable-whole-alphabet-banner.html along with scrapbook paper backing.
I designed the favor tags in Open Office with pinwheel clipart.
The birthday boy's high chair. I love the hat & pinwheels across the front.
You can save a lot of money by doing things yourself. I'm a working mom with a 1 year old and by starting early I was able to make most of the decorations on my own.