Help!Help!!Help!!!

Help! Help!! Help!!! I drive a Hyundai Sonata which just hit 100,000 mi last week. I bought the car in Dec. 2009 with about 82,000 mi. I work part-time and am currently a grad student so there is not a lot of $$. I decided to get maintenance work done last week, as I had the finances to do so. I got an oil change and a full transmission flush. I also had: Both rear sway bar links replaced Front brake pads and rotors replaced This was my first time going to this mechanic. Then I went to a tire chain and got two new rear tires as well as a balance and full alignment. I also had my front two tires wire brushed clean. The tires were not rotated. Two days later I got my car inspected. No problems. One day later a terrible noise coming from my car. Like a constant raspy moan from under the car. I also noticed that the wheel was still acting slightly bizarre despite all of the work. It was definitely better but still seemed slightly shaky with a slight pull. I have noticed that the noise starts at about 25/30 mi an hour. It is loud!!!! I brought the car back to the mechanic and he told me it is not the fault of the tire people nor the work that he did. I suspected perhaps the people at the chain tire warehouse mixed something up or broke a part. The mechanic said that the problem is the nut bolt inside of the front passenger ball bearing within the wheel/tire. I was told that it would be about $330 to fix. The part would have to be bought and then brought to a machine shop to be fitted. Machine shop's estimate would be $60 according to the mechanic with the part included it would be about $150. Then with labor included all the way to $330! Would it really take enough time to justify this labor cost? Does any of this seem right to you? I had absolutely no noise problem before bringing my car in. I had it checked thoroughly by this mechanic, checked at the tire place, and then inspected, all with no noise and no reported nut bolt in the ball bearing problem. SOMETHING SEEMS FISHY TO ME HERE AND I WOULD LIKE TO KNOW IF ANY OF YOU THINK IT DOES AS WELL? IS IT POSSIBLE THAT THE TIRE PLACE OR THE MECHANIC WORKING ON THE FRONT BRAKES BROKE SOMETHING OR BROKE THE NUT IN THE BALLBEARING? THE MECHANIC SWEARS THAT IT WOULD BE IMPOSSIBLE FOR HIS SHOP OR THE TIRE PLACE TO BREAK THE NUT BECAUSE IT IS WITHIN THE BALL BEARING. I Called another mechanic who is going to look at the car and he said that he never heard of a nut inside of a ball bearing. When I asked for my car back the mechanic wanted to know why and I told him I needed to get a second opinion. The mechanic then got very eore-ish and laid a major guilt trip about how he has treated me so good and he thought I would be a good customer- he can't believe I would turn around and do this to him. He put 45 minutes driving my car around today and so on and so forth. He asked me to promise I would bring my car back to him if the second opinion is the same. I think he was trying to guilt me into keeping the car with him and I think that also might be fishy. I just don't have money left to get ripped off after putting so much money into my car last week. PLEASE HELP! THANK YOU SO MUCH!!!!!!!!!!

Tires, brakes, rotors, and oil change is normal wear + tear.
It's good, that you called another mechanic to diagnose noise problem.
Keep in mind, this car didn't get 100k overnight, so don't throw too much money at one time.
As you weed out older parts, you will might pick up other noise from bad front struts, or
CV joints.