You can also use the Mobi2Mobi tools (there's a GUI version for Windows). From the command-line, you can change stuff in place by doing:
Code:
mobi2mobi --outfile SAMENAME.mobi --author "Lastname, First" SAMENAME.mobi
Though it gets a bit trickier with DRM-ed Amazon-supplied files, which use the -exthtype headers which have to be changed in a way better described in the MR wiki.