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For early micro nagware/registration/3rd_party_sales_agent stuff, you might Google "Atlantic." I believe they were the anointed successors to CompuServe, which briefly was a sales agent for shareware, oh, ca. 1989.
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FWIW, I think I paid for a couple pieces of shareware (besides TAPCIS) via my Compuserve account in about 95 or 96.