Hi Barbara,

Well, there was an Archebald CAMPBELL born 20 May 1772, Little Dunkeld, Perthshire, son of Donald CAMPBELL and Janet MCINTOSH - this sounds like it could be your man. It may be worth downloading the marriage details from the OPRs available at Scotland's People (see http://www.scotlandspeople.gov.uk), as they sometimes contain the odd clue. The IGI gives the marriage details as:

ARCHEBALD CAMPBELL
Spouse: JANNET REID
Marriage: 08 JUN 1798 Little Dunkeld, Perth, Scotland

Do get back to me if you think I can be of further help.

Best wishes,

Sue