Thanks to nezumimouse for helping me debug my PPP dialup, but it was eventually mcgroarty's advice--Googling for "linux ppp isp"--that solved that one. (I was using "markpasc" for the username when it was my supposed to be my whole email address. Oops.)
10:17pm: Yay! With addition of nameservers to resolv.conf, am on intarnet!!