I want to replace the bumper on my 2002 BMW 325xi. Do-able? (How?)

I have a 4-door 2002 BMW 325i (it has 140K mi. and still runs beautifully). I love this car!!!! That said, the bumper is a mess - it has lots of cracks and broken-off pieces. I keep seeing replacement bumpers on places like Amazon, at very reasonable prices (e.g., under $100). It doesn’t appear to me like replacing my current icky bumper with a new one would be so hard to do. I can fix my own computer (MacBook Pro, 9,1), but I have never done any car repairs, ever. I have several questions:

• Are the bumpers shown on amazon really as good as they seem?
• What would be a good place to buy a bumper? Reasonable cost (including shipping)?
• Is this something I can do myself? I am reasonably handy, but I’ve learned many times it is not a good idea to just assume I can do it.
• If it is do-able, where could I find out the best way to go about it?

Many thanks for any and all help you can offer.

BTW, it’s the front bumper.