BMW Repair: where is powersteering reservoir?, windshield wipers, bmw engine

Question
I have a 2001 525i  last 7 of vin is GX25801. I have several questions regarding my vehicle if you don't mind, please and thank you.
1.Tonight as I left work in FL temp around 69F I had a bit of difficulty I was on 4th level parking garage. my car made a squealing noise when I turned the wheel to the right, i think left also but not sure since garage exit req all rights. the further i turned the wheels the louder the noise. I assumed powersteering fluid may be low since it was a bit difficult to turn wheel at first. but after a few miles noise was almost non existent. I stopped @ store but could not find reservoir to check fluid level?? where is it? manual says see dealer. Is it possibly the fluid level of something else.
2. I have changed my windshield wipers multiple times (done by dealership) but my drivers side wiper wont really clean the lower 1/2 of the windshield. Is it possible that the entire wiper may need replaced? bent? everything looks okay I am a bit OCD about my window being clean so it drives me nuts to not be able to see out of it.
3. I had 75k mile eval in fall 06 I have to change a couple of belts is this easy to do or should I leave it to the pro's. I changed all 4 brake pads myself. I have also always changed my own oil  (yes, I am a girl who works on her own car) but haven't with this vehicle because of having to do the reset and not being familiar with BMW engine my dealer charges me $120 per change, is it cost efficient to do it myself? also I put 4 new tires on vehicle prior to my changing pads(dealer did tires) but I have noticed at 60mph steering wheel vibrates but only at 60 if i am > 60 or<60 it stops, I took it in for rotate and balance and they say it is fine.
Sorry so long hope you can help. Thank you.
Katrina

Answer
Katrina, it is good to see a girl who isn't afraid to get her hands dirty. The P/S reservoir is just the the driver side of the oil filter. Black round little pot looking thing. Usually the low pressure lines leak that are attached to the reservoir. I would replace both lines. One is suction from the reservoir to the P/S pump, you will need two new hose clamps. The other is a return line from the cooler by the radiator to the reservoir, you will need a hose clamp and a pair of O-rings. Also replace the O-ring under the reservoir cap (hard to see but it is there). Fluid should be ATF. Fill reservoir and turn steering wheel lock to lock to bleed air out of system. Fill until you are between the two lines on the dipstick/cap. I would try replacing the wiper arm complete.
You'll need a small puller to remove arm from the spindle.
You could try replacing the belts yourself. They aren't super easy but if you have a T-50 torx bit and ratchet you could do it. Note the belt routing before taking them off. Check the front control arm bushings for fluid leaking or cracking/tearing of the rubber for your vibration.
-Evan