I have a small backyard and a pond (which I might add I love). I started out with a pre-fab pond from Wal-Mart. Then went to a larger liner pond. When I had a question I went to www.gardenweb.com..then go to forums and then to ponds and aquatic plants. They have been most helpful for me.
Check them out and I am sure they will help you with all your questions.
Hope this helps..