I need to create a "Monthly Summary" (in it's own workbook) from many
workbooks on a monthly basis. Each source workbook contains monthly tabs.
The January Summary is linked to each source workbook, cell by cell (for
totals). Rather than do this manually each month, I would like to copy the
January summary worksheet, and then do a "find and replace" - in other words,
just replace the "word" January with the word February, so my new summary
goes and retrieves the totals from the February worksheets. Data in both
source worksheets are in the same cells.

There's got to be a way. Any suggestions. Thanks so much

Have you tried to copy the worksheet then use menu item Edit | Replace,
with option "Look In: Formulas" chosen? Seems like it would work,
unless I'm not understanding your questions.