Need Recommendations for protein skimmer, powerheads and heater

Hello. I've always wanted a salt water tank, and just started
research on how to properly set up the tank, live rocks, etc. Very
overwhelmed with what's involved, and also the initial startup cost.
I figured about $1k, but never thought it would be more like $2k or
more without even adding the fish. I had nix'ed the idea yesterday,
but then thought, hey....why not start by researching and buying a
piece at a time, until I have what I need to set it up. I want to do
it right the first time. I found a couple books I'm going to start
with, and I'd like to inventory everything I need, and research what
brands/models I want.

What would you recommend for the following based on a 55 gallon tank ?
(brand and model/size)

Protein Skimmer

Power Heads

Heater

Do you have a good online resource for acrylic tanks, and the above
equipment?

If I go with live rocks and live sand, is the Protein Skimmer and
Power Heads adequate, or do I also need a mechanical filter?

Do you feel that 2lbs of live rock per gallon is necessary? I've
heard numbers between 1lb and 2lbs, so figured right in the middle
might be good.

Does the live rock decrease the amount of fish you can have in your
tank? If a inch of fish requires 3 gallons of water, but I have
80-110 lbs of live rock in a 55 gallon tank, do I need to treat it as
if it were only a 30 or 40 gallon tank ?

How close to the wall can the tank be, to allow room for the protein
skimmer/power heads ? (will make a difference on where I can fit the
tank and what size/shape I get).

Thanks for your help!
Pam