I use Monogram Wizard Plus, which is basically a lettering software and it does the arched, stacked, etc. fonts. They are now selling individual alphas to download. Love this program and use it most of the time for any type letter embroidery. Think it runs less than $200. You can get Monogram Wizard Plus with Extended Feature which allows you to bring in designs to merge with the lettering.
www.needleheads.com