The hondata s100 looks like it's just an EEPROM which over-rides the ECU's internal ROM.
But, I have no clue on what serial EEPROM programmer hondata's software uses or how much their software costs.

I did run across a book on tuning:
How to Tune and Modify Engine Management Systems (Motorbooks Workshop) on Amazon.

Maybe,
this for EEPROM programmer:
http://www.hondata.com/pocketprogrammer.html

and
this for SW:
http://www.hondata.com/romeditor.html

Note:
The s100 is old tech. The s200 replaced it (and was discontinued Jan 2008).
The s300 replaces both for about $400 upgrade price (four "tech dollars") which includes SW that runs on Windows; the s300 has a USB interface.
You might save yourself a lot of headaches and time using the s300. If anything ping hondata and see what they say.
http://www.hondata.com/s300.html