COPY/PASTE between both open programs, after you select everything from the source file, would get you a snapshot. Double-click on that snapshot and your original document should open (linked): at least that's how Microfost Office products act.
OR
COPY then PASTESPEC command in AutoCAD/LT would get you more options to choose from.
OR
INSERTOBJ command can be used for the longer process of attaching and linking to a file.
OR
COPY/PASTE from the source file into an open MEXT WIndow, no link, but you get the formatting.
Note that with OLE linking, there is a size limit of around a single printed sheet.
Start experimenting: all the above work with more "office" applications but I don't have direct experience with OpenOffice to confirm.