Hi  Trish. When you say you tried your microphone on the same track, does that mean you unplugged your RS-70 audio leads from your interface and plugged your microphone into the same channel to try it?
 
It sounds as though the inputs on the audio channel you are record enabling may not be set correctly. There are a couple of places you can check this. Here's one:
 
1. Select the audio track you are trying to record the output of your RS-70 on.
2. If the Track Inspector is not open on the left of your screen, press "i" on your keyboard.
3. At the bottom left of the inspector, there are two small dropdown menus, one labelled "I" for input, The other "O" for output that indicate routing for the audio track. Make sure the input listed under "I" matches the physical input that the audio leads from your RS-70 synth are running to on your FW-1804 interface.
 
 

That was it Bruce. And now I remember how it was done. Yes! Thank you!
 
Now is there anyone who can tell me how to get this from the computer this wave file is on to my computer in a file I can send in an email so they can use it?
 
Thanks to Bruce and all who have taken the time to help me. Greatly appreciated!
 
Trisha

Glad you got it sorted Trisha:)
 
If you want to send the actual wave file I suggest Dropbox.   It is free and fairly easy to set up (if you don't have it already of course).   You can upload your wave file to it and send  the recipient a link to download it. 
 
Since wave files are quite large,  if you are going to email it you will probably want to convert it to an MP3 first (many servers have attachment size limits). If you do not have a wave editor like Sound Forge or Wavelab,  there are plenty of free utilities that will do the job. Just google 'free wave to MP3 converter' . Others here might have some good suggestions for particular programs.  I have Soundforge and haven't used any others in a while. 

You can use Audacity
 
You also require to download LAME
 
You open the .wav file in audacity and export to .mp3.
Hope this will help.
Regards
Snehankur
 
edit: somehow not being able to put the link to the download webpages

Or export as a flac file

It's true that a wav file can be large, but just to cover all the bases, you can just drag the wave file from Sonar onto your desktop.  It will probably have some funky name, but you can always rename it like any other Windows file.