Sony EX1!!
Haha... nah they're not the most affordable option, there was a bit of a following for the Canon HV20 and HV30 amongst low budget film makers a couple of years back. Since then I've not kept up on what took over but they hung around the 500-600 range. But personally, unless you're doing something seriously professional, I think it doesn't matter much. A lot of 'budget' cameras are of perfectly usable quality, but important things to consider are things like performance in low light, and what kind of storage media you want to use - and also how the footage is encoded. Some formats can be a pain to edit with and need to be re-encoded before you can even start chopping them up!
If you're shooting for Youtube then the best thing to do is make sure youve got something that can do 720P at a minimum (which I doubt is rare these days) and most importantly NEVER use onboard camera mics if you want something to sound good. Now here's the problem - most band videos suffer from terrible audio and one of the things that's often ommitted from budget cameras in order to get people to buy the next one up is some kind of audio/mic input. I get tired of seeing videos on Youtube where somebody is trying to demonstrate their amazing bass or guitar or cab, without realising that the terrible camera mic and poor recording environment make the whole recording practically pointless!
I've done some semi-pro band/gig shoots and the cameras I've used have usually had XLR inputs that cover audio, but I've always got a trusty Zoom H4 to cover my back just in case! So if you want to do some proper recording then some kind of digital audio recorder is a handy thing to have