another option:
http://www.core.com/
corecomm took over stratos in cleveland. i don't have any experience with corecomm, but stratos was rock-solid and hopefully that tradition continues. it's probably worth checking out.
this is all good if your sister isn't getting a second phone line for a dedicated internet line. if that's her plan, though, then you might want to consider something like Cox cable internet (
http://www.cox.com/). it's cheaper than the cost of dialup + a second line, and it works well (my family in cleveland has it.. in fact i'm on it right now). they even make it cheaper if you already have cox cable for your tv.
no, i'm not a spokesperson for them ;c) i just like saving money
edit: also check out
http://www.apk.net/
another very solid company with good dialup (and dsl), plus it's cleveland-based.