InfoMagic, Inc. One of the major CD-ROM Vendors. They carry a wide variety of material on CD. Relevant here would include:
PHT was a "CD-ROM house" similar to Walnut Creek and InfoMagic. Particularly notable for producing TurboLinux.
They appear to have moved from "producing and selling" to just producing; many of their products are being sold through Walnut Creek.
German distributor of the Debian distribution.