You may read my last post on Y-DNA for Mennonites for the beginning of this series.
Next Steps. Whether or not you have already tested your Y-DNA, you should download the Excel spreadsheet (table) mentioned at the beginning of this web page. You can at least see how many different groups there are with the surname(s) you are interested in. Just be aware that there might be more surname groups discovered as more men of your surname get tested. You might get lucky and see that a descendant of one of your ancestors has been tested already.
Next read the discussion that Tim Janzen wrote for most Mennonite surnames and their groupings. And if you have one of a few Mennonite surnames that are commonly confused, you'll want to read this page.
Getting Tested. Currently Family Tree DNA is the only company that tests Y-DNA; and since they have a monopoly, their prices have stayed high while the prices of autosomal DNA have dropped as competitors have come into the market. Getting the 37-marker test currently costs $169, and the 67-marker test costs $268. The 37-marker test is a good place to start, and you can upgrade to the 67-marker test later if you need to.
I've only tested the Y-DNA of two lines, my own and that of my mother's brother, so I have the lines of two of my four grandparents. I would do more if it weren't so pricey.
Remember if you are female, you can have a male relative tested for you. It just needs to be a direct male descendant of the ancestor that you are targeting. And this applies to males who are testing anything but their direct paternal line, as well. So I could test my mother's brother to get results for my maternal grandfather.
Leave a comment telling us about your experience with Y-DNA.