Humming noise when accelerating

Great information from everyone. Thanks. I consider my knowledge to be intermediate, I find working on the car to be fun and do it more as a hobby and to save a $ here and there. I have never had to do anything with a muffler before. It does seem doable but I have given my shop a call to see what they would charge. If it is $150 that is worth not screwing somethign up. I will let you know the outcome. Thanks