my sister and I also make diaper cakes. We have 3 made right now just waiting for a home. 2 of them are 3 tiers for $60 and the 3rd one is a 2 tier for $40. We can custom do pretty much whatever you want. For one lady, we made 2 matching 3 tiers (one for baby and a spa one for mom, plus a matching corsage). She loved it. check our site out at www.bumblebeebaby.etsy.com or www.bumblebeebabyboutique.com
For napkins, plates... all the other stuff, I like Card and Party Factory or Party City.