Using our SynPDF library and a public domain THtmlView component, and discussion with some of our users, we were able to make a html to pdf conversion tool.
Synopse PDF engine is an Open Source PDF document creation library for Delphi, embedded in one unit. It's used in the 1.7 version of SQLite3 framework, for creating PDF files from reports.
Among its features, you can use a true TCanvas to create the PDF, and embed True Type fonts subsets. Of course, it's Unicode ready, and licensed under a MPL/GPL/LGPL tri-license.
Implements TGraphic descendants able to load and save GIF, TIF, PNG and JPG pictures, using the GDI+ library. Freeware Opensource component, licensed under a MPL/GPL/LGPL tri-license. Works from Delphi 3 to 2010.