Hi Michael, welcome aboard. You can search for a surname or a full name from most pages (including your own profile page) just by entering the names in the search boxes at the top of the page. From the note on your profile it looks as if you already know a number of your ancestors, and if they are not already profiled here you can add the profiles yourself and help to expand the tree. Here there's only one tree and (hopefully) one profile per person.
If I'm missing the point of your question, please post again and I or someone else will take another cut at it. Good luck!
