Steve, if you want people to be a cheering section for you, well, asking structural questions on a construction newsgroup is not the way to go, particularly if you're not prepared to listen. You have not received a single useless reply yet.
As far as it being your house - no mortgage? The mortgage holder would be extremely upset to find out that you've made major structural modifications without pulling a permit. But even with no mortgage, you should be concerned as least as much as a bank would about not cutting corners on your own home.
I took the opportunity to cross post this reply. Since you've asked this question on both groups without crossposting (cross posting is not always a bad thing - it's bad only when it's to non-related groups), you are not allowing people to see the replies you've received and given. Partial information won't help your cause.
Remodeling _is_ building. If you modify the structure of your house you are required to pull a permit. Other factors will trigger the need for a permit, but a structural modification always requires a permit.
If you were in an area that didn't require permits - which, from your reply, you're not - you'd still be foolish to skip out on an engineer's review. Your picture shows more information, but still lacks critical information. Which way does the ceiling framing run? What are the required design loads? Are you in an earthquake or high wind zone? I could keep asking questions, but hopefully you've caught my drift. Only someone who has seen your house, inspected the current situation, and is familiar with you local code and area can design you a solution.
Beginners often mistake the strength of the beam as being the only factor in removing a wall. It's not - not by a long shot. The bearing area of the supports, designing connections to transmit loads other than gravity, adequacy of foundation supports, etc., are all critical. Simply picking a beam that can support a specific load is just a start.
You may have overestimated the cost and underestimated the value of an engineer in you situation? Have you called around to get an idea of the cost?
R