I really like the discussion here: http://navelgazingmidwife.squarespac...homebirth.html
The post links to some other posts as well that have good information.
I think it is also very important to talk to others who have used the midwife. And of course if you ask the midwife for references, she'll give you the best ones. You really want to know if there are mamas who had negative experiences or were dissatisfied, and unfortunately, it is really, really hard to get to this information. If you happen to live in a state with official regulation for HBMW, this should at least be a bit easier. I'm not trying to be grim or anything, and I like to think the best of people, but MWs are making a living at this, and if they have had unhappy clients, they aren't very likely to tell you about it, kwim?
I'd also add some questions like:
~Have you ever had to resuscitate a baby?
~Have you every had to resuscitate a mother?
~Have you ever personally encountered a serious PPH and how did you react?
MWs train in normal birth, which is great, except the thing is, we aren't really paying them to handle our normal births, we are paying them to know when are births *aren't* normal and to advise us when to seek more advanced care and to provide emergency support in the interim. I want to know that my MW is skilled at identifying when something leaves the realm of normal and providing emergency care until more skilled care can be attained. If she's read about emergencies in a book and taken CPR classes, but never had to use those skills irl, she isn't safe enough of a provider for me personally (but of course I totally understand we all have different thresholds of safety - I'm just trying to give you some things to consider as you work through this). Keep in mind that answers to a lot of these questions are "easy" to have good textbook answers too, but that doesn't necessarily equate to real, hands-on skills. These are the things I want to evaluate when talking to a midwife, personally, and try to come up with questions to this point.
I hope that helps you some as you put together your question list :-) GL, mama!