I would also recommend that you take a look at pelicanparts.com
I have completed two brake jobs with parts I purchased from them. Whatever you do, DO NOT get Ate brake pads (Ate makes other brake products that work fine, it is just their garden variety brakes pads that are insanely dusty). They release so much dust that your wheels will look like you drove through a coal mine
Changing the brakes is not hard, but if this is your first time, be patient and do things with plenty of time and pay attention to detail. You should be fine with a DIY from bimmerdiy.com or even pelican parts. I also recommend that you get the Bentley Service manual for teh E46. I think it runs anywhere from $50 to $99 on Amazon with free shipping. It is absolutely worth it. Don't moan about being a student and not having that kind of money. This is an investment. I was a student too when I bought the Bentlyey for my car.
Do get a new pad wear sensor. It is simply good practice. I know you may be trying to save money, your income being limited and all, but it is best to take good care of your car.
One last thing: if your pads are worn down to the point that you have metal-to-metal action, you should take care of this ASAP.... as in yesterday!
Best of luck. Do ask if you have any more questions.
Once again, welcome to werkz