Once you’ve gathered a list, put together a template outreach email (as you’ll be doing this over and over) that’s short and clear with expectations. Tell your potential interviewee who you are, what your podcast is about, and what you’re asking of them. Do a few test interviews with friends and family to make sure everything is being recorded at the quality you want and then book your first episode.
I’ve been doing surveys now for about 18 months, but when i first started i, just like yourself, carried out a lot of research about all the different survey sites and slowly but surely i discovered the best ones to join and now i’m receiving quite a good monthly income from them, but after saying that i am a member of a large number of survey companies and some days i receive that many emails that sometimes i find it hard to keep up with them all, but it is worth it as it’s started to pay off. I’ll not mention all the survey companies i’m with because there’s far too many, but some of the better one’s are Global Test Market, I-Say, Toluna, Mintvine, Your Word, My Survey, Swagbucks, etc, etc. What i do is i keep trying new ones all the time and then i keep the good ones and get rid of the not so good.