If genealogy is the art of looking for a needle in a haystack, then helping your researcher figure out the best haystacks to search for you can save both time and money. Give all the detail you can, because what might seem unimportant to you can be very informative to someone else you knows your ancestor's former "stomping grounds" well.
A clear, concise query greatly increases the odds that a researcher will be able to track down your elusive ancestors and maybe fill in some information you have given up on finding. You need to include all you know about the person you seek--any of the dates of birth, marriage or death you already have, any information about places in your ancestor's life....
I have gotten queries as vague as, "My ancestor was John Smith and he lived in Quebec. Can you find him?" (I'm not kidding, I have gotten letters like that.)
Here's an example of a clear query:
I'm looking for any information about my ancestor, Benjamin Simmons, born about 1787 in Devonshire, England. He came to Canada in 1816, settled in the Hull-Aylmer, Quebec region and was married to Gertrude Losee (date unknown). Gertrude was the daughter of Joshua Losee and his wife Catherine Van Camp, UEL who lived in Carleton Co., Ont. I found a baptism for the couple's first known child, Sarah, in the late 1820's in Methodist church records in Hull. According to Anson Gard's book Humors of the Valley, Benjamin died Jan. 1, 1837, but I have not found another source for that information.
Attach a family group sheet showing Benjamin, his wife, what you know of the children and you have made a clear query which shows all the gaps in your tree. If you have a sheet for the generation before either Benjamin or his wife, then attach that too--you never know where information will turn up.
For example, one gentleman sent me a query about an offshoot of his Heath family and included a family group sheet.
I noticed that his great-grandparents' marriage date was missing. He had given up on finding it and hadn't queried me directly about the marriage; however, I had it in my database. Without the family group sheet, I wouldn't have been able to share this important piece of information with him.
small caveat to all this. I live in a very rural area with only
dial-up access to the internet. Please inquire before sending me
files larger than 50K.