This is too vague a question. Depends on if it is on a graphic, logo, position on page, on an article resource box, etc.

Marketing Experiments or Marketing Sherpa ran a test and "Continue for more" works well within text. Click here is always a good one but the only way for you to tell for your market is to TEST TEST TEST. Always use best practices and lessons learned (niche specific) from the start though. So I would start with the "Click Here"

this is best practice for online media buying and i preffer to do these sord of marketing however it depends how is your presentation if some thing is now coming with free isnt a good way all you need to do is target the right audience.

Not EXACTLY what you're looking for but pretty closely related case studies you should definitely check out: Case Studies | Mr Green

I would think your sales copy is the primary factor in conversions, regardless what the clickable anchor text link says.