NetZero might not be the most Linux-friendly ISP out there but, back in the day, if you called and asked for regular PPP credentials they'd give 'em to you. I did this twice for Windows users that had machines that were so antiquated and underpowered that they struggled to simultaneously run the adware and a proper IE session. Tested the credentials w/Linux's pppd, and they worked just fine. The only thing that might prevent this from working in your case is that they were both paying customers and the fact that all this was 2-3 years ago. Also, be prepared to lie and not tell them that you're using a *gasp* unsupported operating system - Obviously a $0-$10/month dialup ISP isn't going to be getting the cream of the tech support worker crop, so far as their ability work with multiple OSes goes.
Worth a shot, if you can't find anything else local.
Sean Crago Kathmandu