I honestly wouldn't be leaping into this business right now. I have been a writer for 20 years now, including many years as a writer and editor at a publisher. I was in charge of a start-up publication and I can tell you it's a whole lot of work and risk, even if you have an audience lined up to begin with (we were spinning off a specialty area of our main publication, so we had the audience/mailing list). That publisher eventually switched to doing online newsletters and now focuses primarily on research.
It's not a good time in the publishing business. Reporters and editors are being laid off left and right.
Before you start anything, I'd hire a research firm to investigate your target audience and really see if there's demand for your idea. You also need to understand your competition, pricing structures, production and printing costs, staffing costs, mailing list acquisition costs and potential ad revenue sources.
Your best bet may be to develop a business plan and pitch it to an established publisher in a similar niche.