question Best idea to sell Accountancy dot com

Consider visiting or advertising in a trade show targeting accountancy.

I may also think about advertising in an accountancy journal.

I don't believe individual practitioners or small accounting firms are going to bite but perhaps one could target national organizations. In the US - AiCPA, IMA or perhaps publications such as the Journal of Accountancy or Strategic Finance (formerly called Management Accounting and published by the IMA). State Boards of Accounting probably would have little use for it but maybe a top school of Accounting would be open to a lease arrangement. It could give them a degree of prestige as they are battling for nationwide rankings. The Big Four firms might have some interest - Deloitte, KPMG, Ernst & Young, PWC (Price Waterhouse Coopers) as their competitive nature would not want one of the other firms acquiring that name.

One would probably have to use LinkedIn or cold calling key contacts. However, on the inside cover of Strategic Finance I can see contact emails for the editor in chief and national advertising managers.

One selling point of targeting the IMA (Institute of Management Accountants which administers the Certified Management Accountant exam) is that the CMA designation continues to be less recognized than the CPA designation even though the exam is just as difficult and is more applicable to the type of work the vast majority of accountants do (most are not in public practice).

A small ad in the business section of WSJ, could also draw the eyeballs

Surprising that such an avid out-bounder is calling it "spamming". That's gonna break some hearts.

As for advertising as mentioned above, I've found it to be expensive. On top of that, the ads must be articulately crafted and well positioned. That's just to get to 1st base.