So, do not hesitate to ask for help. Instructors wonder why students wait until the last few weeks or few days of a course to express a need for assistance. By that time there is very little that can make up for an entire course of needs. Now, students do need to understand the limits of assistance that an instructor can provide. Of course that is not true.
Most instructors have a policy of answering their e-mail twice a week.
In some cases they may answer once a week. They may even be out at a conference or other business commitment for a few days. One of the most effective forums for communications that overcomes many problems is to post course questions and answers on a bulletin board or electronic discussion forum on the Web. That way, one student's question benefits the whole group with the answer. Also, course forums can be accessed anytime, anywhere and can even easily be updated from out of town or anywhere there is Internet access.