Bought the signalink, basically a separate soundcard to try to send email on ssb. I have an old kenwood tkm 707. After much learning, finally was able to send and receive email via HF. Not bad for $99.
Using RMS Express (Winmor) and a few other free programs for calibration. Definitely not beyond the level of the median IQ.
Tigertronics.com is the hardware site and winlink.org is the software. I think you need a ham license to do this.