For heavy file traffic, i'd consider Dropbox. It's like having a folder on your desktop that both of you can access (up to 2Gig starting). That way, whatever ya'll put in this folder, either of you can access anywhere this program is installed. Program = free. Space up to 2GB. Works seamlessly.

http://www.dropbox.com/

WF

I used to work in on an IT help desk which used Outlook and we had nothing but problems with it. let's face it, Outlook sucks plain and simple. It destroys formatting and tries to change everything to plain text. How about saving your files in MP3 format. I have sent large files over 4mb via email many many times. Some emails had 3 MP3 tunes which went through OK. A lot depends on the capacity limitations of your email server. I also have Garageband on my iMac. I set the preferences to save in MP3 format then export it to iTunes. I than simply drag the MP3 file to the desktop and attach it to my email. You should use another mail system and your WAV files just might go through. If they don't then try MP3 format. Good luck.

With Mp3 192 or better 320 kBps settings you won't loose too much sound quality. With FLAC you'll end with about half the size, and no loss at all, but you and the receiver need the software to change them back to WAV or AIFF if you use a MAC. - NOUT

Thanx all.
Dana, I stumbled upon that Garageband/iTunes option just last night while searching Youtube ( 'WAV to MP3 conversion' ). I'll give it a try today. Be interesting to see what size file I end up with for a 3 - 4 minute song with 4 tracks of instrumentation within the Garageband file ( drum beat, rhythm guitar,occasional lead guitar and a little slide/simulated pedal steel sound ).The next song I do will have a vocals track also.

If I can get them down to Outlook email friendly size ( MP3 quality isn't the priority as it's only a backing track for home practice use )then I'm up, up and away.