I doubt I have a bigger brain than you do but I will attempt to answer your questions based on the numerous articles that I have read on the subject.
Did Congress approve more than was the minimum needed?
If you ask Congress they approved more than the minimum needed to avert the crisis. The bailout is to be paid in two installments, $350 Billion that Paulson has been distributing and early next year if he (or his successor) needs more (and I'm sure he (or she) will) then he (or she) will return to congress to ask for the rest of the bailout money.
Did the banks end up not needing so much?
That's impossible. If there is money available the banks will find an excuse for need it. There are actually stable banks that are applying for bailout money just so that they can buy up other banks.
Is there any oversight over how the money has been/will be spent?
This was one of the major blunders that congress made when they passed the bailout, they didn't ask for enough oversight over how the money is to be used. The bailout bill was sold to congress as a way to buy up the mortgage backed securities, to date I don't think the Treasury Department has bought any of them, instead they opted to buy equity stakes in the banks. Because Congress didn't ask for any real oversight all they can do is bitch whine and moan over how Paulson is misusing their money, but when you hand someone a virtually blank check you don't get to dictate how the money is to be used. Idiots.
Has there been any benefit to the end-users yet?
I have a feeling this one will depend on who you feel are the end-users and who you ask. If the end-users are the struggling home owners who are defaulting on their loans, then no they haven't been helped. If the end-users are small businesses looking for loans to make payroll, I don't think they've been helped either. If the end-user are banks looking to buy up other banks then some of them have been helped.
Is it right for the treasury to allocate funds for the automakers after Congress failed to pass new legislation to do so?
Again this depends on who you ask. If you ask me I don't think any bailout should have been passed, but since this one was I certainly don't think it should be used for the automakers simply because the bailout was for banks and the automakers aren't banks.
It makes me sick how my money is being mispent. I'm one of the responsible ones. I spend less than I make. I have a fixed rate mortgage on my house. I own my cars. I don't have a credit card. Why can't the government act AT LEAST as responsibly as me?
Your idealism is showing. Mine shows rather often as well if that makes you feel any better. The real question here is did you vote for anyone who was in favor of this bailout? If you did then remember this when they are up for re-election and vote against them. The only affect we can have on this situation is to pester our representatives with phone calls and e-mails and failing that with our votes when they are up for re-election.