Probably Period Impressions (google for vendors). Petticoats in the 1840s are fairly basic with not much need for a pattern besides measurements. You can cut three or four fabric panels (depending on fabric width), sew them together leaving a long, hemmed opening about 12″ long in one seam. Put in the hem and set the top onto a waistband with pleating or gathering (gathering was more common as it helped with the fashionable bell shape of the skirt). You’ll want two to five petticoats for a good silhouette. The bottom layer is generally a corded petticoat. Other petticoats can have deep and/or multiple ruffles to help with the silhouette.

Jennifer,
Do you know where I can purchase a pattern for the petticoats worn in 1845? I have an 1845 German dress that I would like to make accurate petticoats for.

Chemise
Drawers – most women were wearing them by the 1840s
Stockings & either walking boots or slippers
Long corset with hip & bust gussets
3 to 6 Petticoats – underpetticoat, corded or quilted, ruffled, plain
Skirt & Bodice or Dress if the two were sewn together
Undersleeves
Chemisette – optional and depending on style

I was wondering if you could tell me the sequence of clothing for a lady around 1845. I’m trying to enter a contest and have to be authentic as possible. I can’t find anywhere that just lists the layers-pantalettes, chemise, corset etc. Thanks! Any help is much appreciated.