Any files that are related should be grouped together and compressed into a single compressed file, such as zip, or binhex, or whatever compression you use. Also, send email to me describing the files and how you think they should be presented on my page. Your description should include the name(s) of each file, the format of individual files, and the computer platform where the files were created, i.e. Mac, PC, or UNIX. If your mail program allows/does it, attach the file to your email as a MIME attachment. If you have a problem with doing this, try uuencoding it. If you are having a problem with any of this, let me know, I can probably help you.
As to formats for text. I have the following preferences in order of preference.: HTML, ASCII, RTF, MSWord up to and including 97 and version 5.1 for Mac, WordPerfect upto and including 6.x. The reason it's in this order is everyone can read HTML and ASCII, and I can convert ASCII and RTF to HTML. As well, I can convert Word and WordPerfect back and forth, to and from different formats as needed. I would prefer spreadsheets in Excel format, so that I can at least examine them. Or if you can put them in a format that I can read in Excel97, that will work too.
And remember, these files are to be for downloading, or reading online(which still means it's downloaded on the web), try to keep their size reasonable so that others don't have to spend all day trying to download them.