"When I prepare spaghetti noodles, I drain them in a colander and do not rinse them. When I put them on a serving plate and spoon the tomato-based sauce over them, a watery puddle forms in the bottom of the plate!"
Actually, that puddle of water simply got trapped with the pasta in your colander. Here's a very easy fix: when you drain the pasta in the colander, shake it a bunch of times, allowing the noodles to toss around. Water trapped between the strands will get a chance to escape. The more you toss the pasta over the colander, the less water you end up with on the plate. It also helps to use a nice big colander.
See our collection of pasta recipes if you need new idea for serving pasta.