Hi, have a quick search around lots of recent threads have hopefully got some stuff of interest which might help you (if you haven't already read them). What sort of budget are you looking at?
HDV ( = hi def on tape) is generally easier to edit on PCs than AVCHD ( = hi def on hard disk or memory card), although AVCHD is by no means impossible with a pretty high spec PC, and the latest iMovie on Macs apparently copes well with AVCHD - see
this thread.
For HDV consumer cams, the Canon HV20 (around £700) or previous model HV10 (cheaper), and Sony HC5 and higher spec'd HC7 (£700-£750) are worth looking at. Sony also make underwater housings ("sports packs") for their camcorders which I've seen good reports on (think the HC7 takes the SPK-HCC, anywhere up to £200!).