I am buying a digital camera for normal purposes, but i would also like to buy underwater housing for it. Does anyone have any suggestions on what camera is a well rounded camera that takes good underwater shots? I was thinking along the lines of canon SD550 or SD600.

Welcome to the board Ben.
Whatever camera you choose, I would suggest you find one that you have full manual control over. Presets work fine above water but are lacking for UW use. If you want great pictures UW you will need a camera that will allow you to take manual control and you need to learn to use the manual setting. Also, plan on a strobe, you will need it. The internal flashes are pretty much useless under water except for macro shots.

from what i have read here on BT it sounds like one of the olympus point-n-shoots housed in one of the PT-xxx housings is the least expensive option for some good pics.

when thinking about an external strobe you may need TTL functionality in the camera and an external connector on your housing so keep that in mind.

if i had it all to do over i would start with a digital SLR and a macro lens in an ikelite housing and lens port - then add an external strobe at a later time if on a budget...

definitely try to search this board for olympus information...

good luck,

TTL and an external connection are nice but not a requirement. Lots of us use a fiber connection and the strobe either in manual or a simulated TTL (STTL I think Inon calls it). Both work nicely.