If you are searching for death records there are a number of places that you can look for them in Michigan and Kalamazoo in particular. If you have many ancestors who died in Michigan you can count yourself lucky that civil registration began in 1867, unlike many states in which birth, marriage and death records were not required until after the turn of the century. Before you anticipate finding every death record occurring during the early years after 1867, you may want to curb your expectations. In my experience, birth and death records appear to be spotty for a decade or so.
A good place to begin is Family Search. You can start with the name and county and/or state and see how many results your search generates. On the left margin of the screen you can narrow your results by adding more information. Just remember, less is more. If you add too many search criteria you may miss what you are looking for. Parents or birthplace, for instance, may be listed as “unknown” and if you fill those in, the result may not show up or be so low on the list you won't find it. Also keep in mind that the records here have been transcribed and I'm sure we've all seen incorrect transcriptions.
If you believe your people died in Kalamazoo county you may also want to check www.kalamazoogenealogy.org. I often peruse the entire section of the index where my surname of interest appears to see if I can find any other family members. Remember that the death index (though not the records) goes through 1975 so you will probably have more luck finding mid-century deaths than at FamilySearch (at least in my experience).
You will find death records at Family Search and www.kalamazoogenealogy.org, but if your people died in 1897 or later there should also be a death certificate. Why look for both? Because some information may appear on one and not on the other. For instance, death certificates often list place of burial (something that Kalamazoo death records don't include). Another reason to seek both death records and death certificates is that a piece of information may be legible on one record, but not on the other. Seeking Michigan has digitized death certificates from 1897 to 1920. I always use the advanced search as anything else leaves me hopelessly buried in data. It is useful to remember that the search algorithm here does not search for name variants. If you search for “John” it will not pull out “Jon” or “Jonathon.” I often search on the last name and county to start. Just keep trying variations of your search until you find what you are looking for. One technique I have found useful both at Family Search and Seeking Michigan is to search on parents' names. If the names are uncommon try searching with one or both first names only. Or to identify potential sisters of a male relative try searching on the father's surname. This allowed me to locate two sisters (whose first names I didn't know) for one of my people. A look at the informant (as well as subsequent information found) helped to confirm the connection.
For more recent deaths, Ancestry.com has a database of Michigan deaths from 1971-1996. If you don't have a subscription, ask if your local library does.
Unfortunately, online death records for Michigan are pretty spotty during a good part of the 20th century. You may have to get creative or be patient. If your ancestors died in Kalamazoo county you can use the index at kalamazoogenealogy.org to at least determine the year of death. You can also search through the Kalamazoo County Clerk's office online. Click on “search for vital records” and follow the prompts. The results here are limited in scope, but you will usually get a specific date of death. Armed with this information you can search for an obituary at the Kalamazoo Public Library in their Local Newspaper Database. Even if an obituary has not yet been indexed they can be ordered through the KPL for just $2 if you aren't able to go in and look it up yourself.
Just a couple more notes on death records. Sometimes you really have to dig to find what you are looking for. From the KPL index I found an obituary for one of my people, but I hadn't found a death record under her surname. As the obit indicated she died in Kalamazoo I felt there simply had to be a death record. Since I now knew when she died, I went through the death records page by page until I found it. Whoever had recorded the information wrote her name as Harrington instead of Harrigan (her maiden name confirmed her identity).
One other instance highlights the importance of thinking about your findings. Before I found the newspaper article describing how poor John Flynn bled out after he fell from a scaffold and his hod pierced his side (see my post Casting a Wide Net in Newspaper Searches), I had two, yes two, death records for him. I'm still not sure how this happened, but at first I was unsure which was the correct record. The first record was entered into the ledger on 4-30-1888 with the following details: John Flynn, death date 6-22-1887, age 64, married, died in Ann Arbor “in fall from 6th floor of building,” born in Ireland, parents John/Mary Flynn, mason. The second record was entered on 6-1-1889 and had the exact same information except it listed the death date as 6-18-1888. In my opinion it was just too much of a coincidence that two men with all of the same identifiers would die in the same manner a year apart. My working hypothesis was that it was the same man and the death had inadvertently been entered twice. But which date was correct? When I stopped to think about it, it became clear that the first date had to be the right one. Unless the clerk's office employed a psychic, there could be no death record on the books before the death actually occurred. As with everything else, it pays to think about the information you are finding.