How To Access Information From A Table

I am familiar with Excel, but have a hard time figuring out the best approach to a problem. I have a form where I have a drop down list to select a specific pipe material for the specific work (see Water Piping.JPG). Once I select this material, I would like it to pull the specific prices for each pipe size from another worksheet (see Pipe Pricing.jpg) for that specific material and specific size. Basically I am looking at a way to quickly change the material and see the differences in price between various options. I have approximately 20 different material types and pricing for each of these. The only thing I have done in the past was an If/Then statement to do this for a couple of pipes, but it got to be vary cumbersome.

I have attached a couple of images from this issue showing the information I have.

Any thoughts on a more efficient way to accomplish this task?