Check a local dental school... or community clinics... I know the word 'CLINIC' has a negative stigma attached to it, but where I'm from, we have a dental school and a community clinic right next door. We (dental students) work at the dental school and charge a lesser fee than private practice (well the SCHOOL charges it...wel don't get a dime..just the learning experience)...and the clinic..well several of our faculty (dentists) work there and the clinics sometimes use 'sliding scales' based on income. Try those options...see what you come up with...
And yeah... dental work won't be cheap..I'm sorry!!
Unfortunately, I don't think that cheap and dental work go together. Do all of them have to be done ASAP? What's the emergency?