Prepending to different file types?

Question

Hi,

This may be a fairly straightforward one, but not having done much work in this area I just wanted to throw it out there

I'd like to take a file, and prepend some data to it. This has to be done for several file types:
PowerPoint presentations (.ppt) - take an existing presentation, and insert a new first slide
Word Documents (.doc,.docx) - take a word document, add a new first page
Sound Clips, Podcasts (.mp3,.mwa) - take a clip, and prepend a new start section
Video Clips (.wmv,.mpeg) - same as for sound except with video

Anyay, you get the general jist!

Is this a case of just using a StreamReader and Streamwriter to create a new file based on merging the 2 existing ones??

Thanks