If you are looking for truly-qualified Perl programmers, your true problem is never going to be finding them ... it’s going to be finding a free time-slot in their busy schedule. If you are not getting bites from “the right kind of fish,” then change your bait.
Okay, some things can’t be avoided ... some minnows will strike indiscriminately at everything that is thrown into the pond. But unfortunately, 99% of that is just noise. If you are not getting prompt “strikes” from the kind of fish that you are looking for, then you need to make sure that your inquiry both adequately reflects what you need, and that it is of a nature that will actually attract the attention of those fish.
And what is going to attract them? A clear description of a business-problem that they know they can profitably be engaged to solve. But also, a clear indication that you know what the problem is, and that you have both “the Money, the Authority, and the Pain” to actually address it. (If you don’t have all three, then, pardon me, you are “just fishin’.”)
For example, “knows object-oriented Perl” does not actually say jack squat (pardon me...) about why you need that. Therefore, write your advertisement so that it mostly talks about “what you need, not what you need Your Ideal Candidate to have.” Assume, from the outset, that you are hiring a true professional contractor, not an employee. Don’t talk about the individual you want to hire (or to engage): strictly talk about the job that you have to do, and assume that a professional software contractor knows his or her stuff. Don’t waste your time, or theirs, saying stuff that is roughly equivalent to, “competent with the use of a hammer and a power saw ... knows how to cut a two-by-four to proper length.” (And please do not take offense at this, because I mean none. “This is the Internet,” so I feel that I can just speak plainly.)
Also, please do not assume that the individual (or more likely, the LLC) which you engage must be “in NYC.” Most likely, it won’t be. You need work done. “You care only about the results obtained.” You are severely limiting yourself if you place limits on where those people physically reside. Write a contract with an LLC that guarantees that you will obtain what you actually want your corporation to receive from their corporation. “ Just like you would do with The Cable Guy.™ (And if you do not yet know what that should be, that is in fact perfectly to be expected: therefore, your first contract should be for expert and impartial consultation.)
In the traditional job-seeking scenario, you put out your bait, and everyone (on Monster) strikes at it, and you get to sort between them. You pick one, then find office-space and wrestle with I-9 or W-2. But the sort of people that you are really looking for don’t play that game anymore, because they don’t have to. Strange as it may seem, you need to attract them. These people do have the ability ... in spades ... to solve whatever business problem you may have. Therefore, describe it. You are speaking to people who are in the business of doing this kind of work, so you are dealing with LLCs, not people. They’re out there, and, in case you haven’t already guessed, they’re all right here. They are going to qualify you. They are going to calculate (very quickly) whether it’s likely to be worth their time to strike at your bait. If they do, take a number ... and be happy.