how much money your are willing to spend.
I agree. Knowing this will go a long way in answering your question.
When I first started doing video in May of 2008, I bought what I call a used starter unit consisting of a TopDawg housing with lights and a Sony DCR-HC32 camcorder. I paid a total of $1000 for the set-up. I have used this on three trips now and have been very pleased with the results. But a system like this has limitations with not being able to do MWB or a flip color correction filter. But like I said, I am pleased with the results and when I and my friends watch one of my trip videos they say that looks great.
But then I come on a site like this and start watching videos where people are shooting in HD with top of the line camcorders and housings with all the bells and whistles and you say, "Holy ****! I didn't know it could look like that!" And believe me it's a night and day difference between what they shoot and what I shoot. But $1000 for them might just be the price of a lens for their housing. In the end they are going to spend thousands of dollars for what they are using.
I guess my point is, like in most things, you're going to get what you pay for when it comes to shooting UW video. I'm in the process now of looking to upgrade to HD with a housing that will do it all and I know I'll be out quite a few thousand when I'm finished with purchasing things. That's the problem with getting into stuff like this. The bug bites you and you get the upgrade fevor and we all know there is only one way to cure it.
So you really do need to decide what your budget would be. A really nice HD camcorder could easily run $800 to $1200 dollars but the price of the housing that camcorder could be used in may be anywhere from maybe $1000 to $4000 and up up up! Then the price of lights could potentially add $1000's more.
I personally think it is more important to find a camcorder first and then a housing for it but understand that you'd probably need to stick with the major brands like Sony, Canon, and JVC etc. to find good housings.
You should also look at used systems. You can find some really incredible deals on sites such as this and wetpixel.com where people get the bug and trade up from what is a very nice system to something top of the line and you can save thousands by doing so.
BDSC