First OFF, Welcome to the forum. As you search around here for information check the archives about a body of water and check the sections about the kind of fish you want to catch. You will soon find a pattern of what fish are in what type of water. i.e: trout in rivers and lakes, salmon and sturgeon in rivers only. Hagg lake is the largest lake near the metro area and gets the majority of the trout stocked near Portland. Anywhere along the bank you can catch fish, the most popular places are near the restrooms!
Tell us a little more about yourself. Where you're from, where you are now and what kind of fishing you have done in the past. We tend to get sidetracked from time to time (OK all the time) and many of us have strong opinions about different topics (not just fishing). So be patient, be kind, take some things with a grain of salt and try to keep it out of the wounds. Most of all have fun.