I had seen this query asked in the scots-l mailing list. Besides the thread here, I found the following via Google.

Here's some more links to check out:

MP3 To Mid Converter - Wave to Midi ,MP3 to Midi, Audio to mid

WIDI

Score Extractor

IntelliScore

Download of a program for Wav to Midi conversion:

Music Master Works

Solo Explorer

Digital Ear

Same question was asked here:

How to convert Wave to MIDI

and:

Freeware Wave to MIDI?