In a lot of cities, and I suspect that NYC is no different, there are gatherings of testers. If you show-up at one you may be permitted announce your position. If you sponsor an event, which at my group that means buying doughnuts for people to eat beforehand, you can usually have a short talk before the event.
Testing positions are very much like other job postings, people apply to them without looking to see if they actually qualify or not. They assume that the more resumes they send out the better their chance of getting hired. If you want an automated way of filtering candidates out, indicate in the posting, usually somewhere buried in the prose, that only candidates who use some specific word in their email will be accepted, and then use a filter to flag those, you'll save yourself having to wade through the mass-responders who are usually unqualified. I remember when I had to review resumes, it was obvious who was qualified for an interview and who was just responding because they needed a job, but it required wading through resumes for hours before a short-list could be found.
I don't know the size of your company, but the last company I was at had a great hiring procedure. They hired a lot of interns and had them report to a more senior staff member. That meant a bit more overhead for the staff at the start and end of each semester, but it was usually worth it with the additional resource for the ten weeks between that time. We usually had one intern for every three full-timers. We would then make job offers to the best interns at the end of their final year. With testing, it's a bit harder since first- and second-year students will often apply for those and not people who want to be full-timer testers. If you can find a school that has a specific testing program, you'd be in a great position to hire them at the end of their education. Just a suggestion for long-term thought on the subject.
Walter