For wind specifically, I know that the general idea does involve a table of some sort to translate the RPM to a power curve that the MPPT then uses to make it's "move".
The only links to DIY that I personally know about are the two I mentioned above, but they are of the "dumb" variety, meaning that they are pre-set (with solar in mind) rather than dynamically changing around what an alternator puts out.
However, the basis of MPPT is the buck converter, so the same concepts apply to both solar and wind, it's just that the wind version needs a brain to optimize it.
My version, which is just the buck converter without "true" MPPT functionality is
here (this goes straight to the pics of the first working prototype).
Her first one (that I modeled mine after) using the same basic design but with additional functionality can be seen just down below mine.
She did a "take 2" synchronous version as well, in an effort to squeeze out even more efficiency. If I were to start over, this is where I would begin, but the asynchronous version (above) worked well enough for my purposes at the time, so I never went into building the second one -
http://fieldlines.com/board/index.php/topic,144963.0.htmlSeems all that would be left would be to set up your PIC to provide the tracking signals to her enhanced version, and you'd be good to go. Mine strictly monitors the input voltage, and tries to keep it at a certain point, with no regulation imposed on the output (other than "float stop" to prevent the output from soaring too high under no load).
She can tell you much more about them than I can; I understand how they work, but the synchronous version is completely her brainchild and she understands it inside and out.
Although, I haven't seen her around lately...
Hope this is of some use...
Steve