Essentially, distribution of your program is grunt work on your part.

Other compression formats may be more appropriate for other operating
system platforms, but as a rule the online community, including BBSes,
online services and the internet, has standardized on "ZIP" compression
format for posting and downloading of shareware programs.

Your program files, including some documentation in pure ASCII text,
should be compressed into one archive and the archive given a file name
that expresses the name of your program and its version number.

          Xword v1.0 word processor  -->  xword10.zip

The pure ASCII text documentation file name can be one of the generally
used names such as READ.ME, README.1ST, or README.TXT. Whatever name you
choose, the file itself should be nothing but pure ASCII text (text
without hidden formatting codes) and contain your copyright,
distribution permissions, a statement that it is shareware, registration
information, the purpose of the program, and how to install it.

An old and widely used standard is to include a file called
"FILE_ID.DIZ" (the DIZ extension stands for Description In Zip).  It
consists of 45 characters per line, 10 lines max, and the first line
should be able to "stand alone" as a short description of the program. 
Originally designed for bulletin board systems, this file has become a
de-facto standard.  A more recent proposal is the VENDINFO.DIZ/DOZ file,
by Rudy Ramsey.  See the link mentioned in the list at the end of this
FAQ.

Once archived into a zip file, you can upload it to BBSes, online
services, and ftp sites on the Internet. You can also send it to CD-ROM
publisher and shareware disk vendors. In most cases, it will be reviewed
by the system operator of site management, and then posted along with a
short description, for user downloading.

Although the actual registration to download ratio has a variety of
factors, extensive distribution is the key to obtaining the highest
number of registrations. As a general rule, the more people download it,
the more people will register it.

Most shareware authors begin by uploading their program all over the
place, wherever they can. This can take hours, days, even weeks.

A variety of places offer distribution of an author's shareware program.
Be sure you read through their information and pick the distribution
service that is right for you. Some services overlap, some do not, some
are free, some are not, some create CD-ROMs, some do not.