See the Spreadsheet and Excel namespaces on cpan. You can get most, if not all, format information from XLS and XLSX files. Since it is not an MS product parsing an MS data structure, there may be some things it does not do quite right, but in my usage, I have found them to be pretty good.

I am using Spreadsheet::Read at the moment as a top-level layer for a spreadsheet reading on a project, and am starting to look at Spreadsheet::Wright as a top-level layer for spreadsheet writing. Formatting is available in both.