Binh's COM notes
Articles on using COM Callbacks and COM threading along with good source code examples.
Charlie's WEB Site
Lots of good information and reference material. D2 and DCOM and OLE bits included
COT Case-3: Borland's Delphi as COM tool
Centre of object technology q&a about Delphi as COM tool
Delphi and Microsoft Office: Automating Excel and
White paper from Inprise, on how to use COM/OLE from Excel with example source code.
Dr.Bob's ActiveX Files
Delphi ActiveForms and One-Step-ActiveX Controls in Action.
How to write COM components in Delphi
Tutorials on writing COM software with Delphi.