How many miles a week are suggested for marathon training?

A lot depends on whether you are a beginner or expert. 35 miles is the recommendation for first timers taking it easy; 70 miles is recommended for those who want to finish near the top. Here is a lot more info on training for your first marathon: http://www.findingdulcinea.com/features/feature-articles/2008/august/Get-Your-Marathon-On.html