Hi belle, and welcome to the Q&A Board!
Don't fret about knowing what to do. It's not an uncommon feeling. There are so many brands and styles and size and costs of digital cameras out there and it can get confusing.
Let me start by saying that we really don't recommend digital cameras at Digicamhelp. However, we can offer some names and models that match as close as possible the features you want.
It seems the four key features you're looking for in a digital camera are:
1- Ability to focus well in low light
2- 6X zoom
3- 3-4 megapixels, possibly five
4- A full song or two so the cam also needs to have decent sound recording skills
Another factor is that you want to keep the total price to around $400, including camera, memory cards and batteries.
You may have to make some compromises because of your budget. I don't blame you for not wanting to spend more if you'll be using it a lot in a high risk area. So let's throw out some options and go from there.
To be honest, with the exception of dSLR cameras, most current digital cameras perform poorly in low light, particularly in dark smoky bar/club situations. I don't know if you're allowed to use a flash in club situations but if so, the tiny built-in camera flash will not be sufficient. You'd do better with a camera with a hot shoe, and an external flash.
"Awesome low light capabilities.”
Hmmm, there is only one digital camera available on the market I know of which fits the bill." That's the FujiFilm FinePix F10. It doesn't have and 6x zoom, but it is excellent in low light as it shoots images practically noise free ("grain free") using up to ISO 1600! You'd rarely ever need a flash. It only has a 3x zoom but it is 6 megapixels so you have plenty of resolution to crop images. It takes an xD memory Card.
You can read user reviews here:
http://www.dpreview.com/reviews/read_opinions.asp?prodkey=fuji_finepixf10Another option is to get an "older" camera like the Olympus C-770 UZ. It's four megapixels and has a 10X zoom. It has a hot shoe for an external flash and takes an xD memory Card. If you shop around online, or watch for sales, you may be able to get it for under U.S. $350. I don't know how it does in low light, and it has no autofocus assist lamp.
You can read user reviews here:
http://www.dpreview.com/reviews/read_opinions.asp?prodkey=oly_c770uzI'm not sure how long either records video and sound or it the quality is good; you'll have to check the specs and reviews. I do know the S2 video records in stereo. It also has a mode to record only sound, with the maximum length limited only to the size of the memory card. It records sound and video up to one gigabyte (about 8 megabytes at full resolution and frame rate). It does a decent job at capturing sound, but it surely isn’t like recording studio equipment. But, imho, the S2 and S2 are par for the course in low light situations, though that doesn’t mean you can’t get stunning shots if the light is right. Image stabilization is a very useful feature in low light.
I hope this helps at bit. If you have further questions, please don’t hesitate to ask.
btw, dpreview has a great database that lets you compare cameras using many variables:
http://www.dpreview.com/reviews/compare.asp