can someone tell me a website that gives a basic rundown on pipe sizes in a residence?

Question

I am trying to find basic answers to plumbing pvc diameters

Answer 1

Local Plumbing codes dictate the sizes used for piping. Each area can change these to fit their own ideas. Basically:
Main cold and hot water runs are 3/4".
Take-offs (lines to each fixture) 1/2"
Kitchen, tub/shower drain 1-1/2"
Shower only drain 2"
Bath vanity or sink 1-1/4" from fixture to wall and 1-1/2" in the wall.
Most take-offs are reduced after a shutoff valve to 3/8" supply tubing.
Main drain line and vent 3 or 4" (normally 3")
Backventing pipe is usually the same size as the drainline and tied into the main vent.
Washer drain 2"
Hope this helps.

Answer 2

You don't need a web site. You got all the information you need from sensible-man. Great answer.