Don't resort to a lawyer first. The vast majority of them are nasty bits of work that are best avoided until necessary. Unless you know a good one or have a lawyer friend.
By all means write him yourself first and if that doesn't work, he desrves what he gets. Whether you want your money and the value of the goods you traded, with interest, or the knives, there really is one best way to proceed. Give him a deadline to produce and deliver the knives, failing which you are to be fully reimbursed. This indefinite waiting bullsh!t has to end. Pick a reasonable deadline:if you don't get the knives by then, you ain't never gonna get them anyway.
I should think that you should write him demanding that he provide you with a reasonable but definite delivery date, which should be no later than a date you specify in your letter, and that if he doesn't meet the date, then you'll expect all your consideration back with interest. The demand may light a fire under his tardy @ss. But at least it will bring the uncertainty to an end.
As a matter of business practice, taking full payment up front without providing anything in return is rather unusual, and pretty lousy. He's taking the benefit of your money with no motive to perform his side of the bargain. It doesn't smell very good to me, but it is possible that there are extenuating circumstances. If he isn't answering the phone and ignores your letter, he better have a real good excuse, to satisfy a judge. You could probably could get your money back etc. now on the basis of a total failure of consideration or fundamental breach, but your problem is that it isn't clear, at least to me, what was agreed to in terms of a delivery date: so you may have to fix a reasonable date by reasonable notice, evidenced by a writing and proof of delivery you could show a court, if you have the patience for that sort of thing.
Or you could let us know who it is and we could get on his case.
[This message has been edited by HJK (edited 08-04-2000).]