A tv and stereo nearby shouldn't be a big deal, as long as you're not blaring it 24/7.
I'm not aware of any breeders off hand, many that come in are wild caught - but they do breed readily in captivity, so I'm sure theres more than a handful of people that have done it. They're just not in high demand like leopard geckos or crested geckos.
I've never seen a giant day gecko over 8 inches. Are they capable fo 10-12 inches? Probably... but I wouldn't hold my breath on it.
Misting really should be a daily thing - I mist when I turn the lights on in the morning, but what you can do is just mist a little extra before you leave. You don't have to worry too much about soaking the substrate, a day gecko will rarely be on the ground to be in it, and it will keep the humidity up. I've been seriously disappointed with every dripper system I've tried, but that would be one way of making sure drinking water was provided. It wouldn't even have to drip very often.
Cages need to be well ventilated, but not so well ventilated that they get drafts, or all the humidity just escapes right out. Real plants are not absolutely necessary. I have a black thumb and can't keep plants alive for anything, so use fake ones. Just make sure you wash off fake ones very well before putting them in. Many times the manufacturing process leaves dust, oils, and other various things on them. Real plants do help keep the humidity up better, and generally make for a nicer looking terrarium. Oh and make sure you get the nylon meshing and not the metal stuff, the metal will rust pretty quickly in a moist environment.
As for other sites... I don't know of anything on day geckos in particular, but Reptile Rooms
has a large gecko owner population, but most of those are leopard and crested geckos, but I'm sure there are other species in respresentation as well.