My usual first stops:
Maine in 1790 project (now up to 12 volumes). Published by the Maine Genealogical Society. While 1790 is later than your question, many of the heads of households profiled were born before 1750 ~ or are linked to parents who were.
The Great Migration project from NEHGS and all of its off-shoots.
The Mayflower "silver" books. Some have been superseded by recent research but still helpful.
The DAR application records in their genealogical research system (GRS). Like the others, the accuracy can be iffy, especially for older applications ~ but it's worth seeing what has already been researched. As with the Maine in 1790 project, the GRS is focused on slightly later records but often has details about the generation born in the mid 1700s.
For anyone Quaker, Hinshaw's Encyclopedia of American Quaker Genealogy is very much a starting point ~ but it can help with locating people and which meetings they attended for a jumping off point to original records. [Side note: Thomas Hill's Quaker meetings website is an excellent tool for locating Quaker records.]
Finally, the major journals: NGSQ, NEHGR, NYGB, TAG, and so on. No sense reinventing the wheel if someone has already done the research.