flash (macromedia):

Open up your .fla file. Go to File > Publish Settings. Check off the Box for
publishing as an HTML file. Then hit publish. An html file will be placed in
the same directory as your fla file. Now, open Notepad, or some other text
editor. Using that text editor, open the HTML file. You should notice some code
starting with <object and ending with </object. Copy all of that. Now, open up
your webpage with a text editor, and paste that code in which ever part you
want.

If you own Macromedia Dreamweaver, you can simply click on the picture of the
flash icon in the Insert Panel and then browse to your file.