I am not sure why the recognizer functionality is not available on all devices. Make sure you install and update the latest Google Voice Search for Android. I believe it installs the latest recognizer. See http://www.google.com/mobile/voice-actions/ it may be helpful.
As Dante Jiang said in Converting speech to text, According to this article, Google Voice Search is what you actually need.
The Android SDK makes it easy to
integrate speech input directly into
your own application—just copy and
paste from this sample application to
get started. Android is an open
platform, so your application can
potentially make use of any speech
recognition service on the device
that's registered to receive a
RecognizerIntent. Google's Voice
Search application, which is
pre-installed on many Android devices,
responds to a RecognizerIntent by
displaying the "Speak now" dialog and
streaming audio to Google's
servers—the same servers used when a
user taps the microphone button on the
search widget or the voice-enabled
keyboard. (You can check if Voice
Search is installed in Settings ➝
Applications ➝ Manage applications.)