Muse testing your niche market?

[JGresh]

Okay, here's something I find confusing. Tim recommends finding magazines that apply to your niche market for eventual ads. Got it. But prior to that, I do testing via Google Adwords. How do I get my niche market to my test ads? I am looking to take a relatively common product (a wallet) and sell it to a niche market (women in the military) based on the design. I haven't started the process of investigating good search terms for PPC, but I'm almost wondering if I wouldn't be better off putting a small ad in one of my niche magazines, where I think advertising would be relatively inexpensive.

Am I making this too hard? Thoughts?

Thanks!