I got my Ph.D. in math in the last year and am currently in the first year of a 3-year research-oriented postdoc at a large public American university. I am finding it harder and harder to focus on research, not necessarily because of teaching, but for various reasons which I don't think are relevant to the question, and I am beginning to think that I would like a career as a lecturer. I enjoy teaching quite a bit, and I think I'm fairly good at it. If, as I originally intended when I accepted the postdoc, I still planned to apply to research-oriented tenure-track positions, I know what I need to do to be prepared for that process (whether at a large research school or a smaller college which still requires research of its faculty, e.g. a tenure-track position with somewhat higher teaching emphasis). But it seems from looking at purely teaching postings on MathJobs that, for example, I will definitely need three letters of recommendation addressing my teaching. I honestly don't know how to go about finding people to write these letters (for the tenure-track career path I would expect to have to get one teaching-oriented letter). I have a teaching mentor who has observed me a couple terms who could presumably write one letter, but I don't know about the other two. Do chairs write teaching letters? I'm frankly a bit afraid to tell anyone at my institution that I'm not sure I want to do research anymore, since they hired me with a reduced teaching load to give me more time for research. I actually really like the place where I am, and think, at this point anyway, that I would like a lecturer position here, but as I'm currently doing a postdoc here, I have no idea how likely it would be to be hired as a lecturer (even with, let's say, an excellent teaching record).
Note that I'm talking about a lecturing position, where the only expectation would be teaching and possibly also service. I'm not talking about the tenure-track jobs with more teaching emphasis which still require some research output (although I guess it's possible, though by no means certain, that the research incidentally produced from my thesis could make me eligible to be hired for such a position). But I think that I really just want to focus on teaching (preferably at the university level).