I second /u/Searocksandtrees' link to the FAQ. Speaking for myself, Patrick O'Brian's Aubrey-Maturin series is generally quite good at conveying the flavor of life aboard ship -- O'Brian read many contemporary accounts of the time period and quoted in some places directly from journals kept aboard ship. His novels do not follow a strict chronological timeline, but the terms used and the flavor of the period are highly accurate.
hi! there's loads of room for more recommendations, but just fyi, you'll find some previous ones in the FAQ
Molly the American Girl Doll! :-P (but really . . .)
I'm currently reading the Nicolas le Floch series by Jean-François Parot which is about a young detective in XVIIIth century Paris. The first six books have been translated in English. The investigations and cases are very interesting, leading you to the slums of Paris as well as to the highest places in Paris. If you like police stories this is definitely an interesting series of books but Parot also shows his knowledge of the time filling his stories with amazing details about everyday life, eating habits, descriptions of the streets and its people.
Though some characters are fictional ( such as Le Floch ) you will encounter some existing people like as the Lieutenant General of Police Antoine de Sartine, Louis XV or his daughters, the Duke de Choiseul-Stainville,...Etc
I highly recommend it because beyond the police scenarios you also make a tour in Paris during one of its more fascinating period. There also has been a TV adaptation though I don't know if you can even find it with English subtitles.
Here is the wiki page of the book series with the list of books.