It depends on the computer.
In the price range you provided, generally, if the Mac is only a couple of years old, you may be OK. It is not exactly the *camcorder* that is "compatible" with the computer (whether Macintosh or Windows)...
Many times (assuming the computer is relatively new), plug the camcorder into the computer using USB, put the camcorder into Play, PC or USB mode (it depends on the camcorder and computer), launch the video editor and Import or Capture or Log and Capture the video (it depends on the editor).
Sometimes, plugging the camcorder into the computer using USB, putting the camcorder into Play, PC or USB mode causes the camcorder mass storage to mount to the desktop. In this case it might be better to copy the video files to the computer and using a transcoder like MPEGStreamclip from www.squared5.com, transcode the compressed video files to something more useful (MOV or MP4). After the trascoding is done, quit that app, launch the video editor and drag the converted video files to the "storage/library" area then edit.
The camcorder usually is computer agnostic - but the software in the box with the camcorder is operating-system specific. This is not much different from the firewire-connecting MiniDV tape days. Just a different process.
If you don't want to edit and just need playback, then download and install VLC player from www.videoLAN.org.
If you want specific recommendations... I like the Canon HF M series (the HF S series is a bit outside your budget). I have used HF S series camcorders successfully with my 5 year old iMac and continue to use Sony miniDV tape camcorders with it...
Perhaps something waterproof (in its case) like a GoPro or Contour is worth a look.