How can I estimate Project Management time/effort for IT Consulting projects?

I'm not a paid researcher, but have done Project Management. This is a
pretty tough question to answer.

It depends greatly on:
--thoroughness and accuracy of specifications (do you have to develop
them yourself or are they handed to you in perfect form, or somewhere
in between?)
--employment status of yourself and the persons who will perform the
work (are they contract consultants or employees? on-site or
off-site?)
--level of expertise of yourself and workers (how familiar are you
with the task? who will pay for you to learn all facets?)

Rule of thumb: Have the worker(s) estimate their time or budget. Make
your own numbers the same.

Indeed...quite a tough question to answer since there is no definite
answer. If you could accurately estimate the amount of time projects
would take you could make a lot of money just doing that for
companies.

The way I usually do it for programming projects is to estimate how
long I think I could do a project without any setbacks (when I say
without any setbacks, I mean total optimal time. Like if somebody
offered you a billion bucks to do it in your estimated time, you'd
just barely be able to do it). Then double that number and change the
unit up one. So for example, I think I could do a project in 1 week if
everything went perfectly. So in actuality you won't be finished
completely until 2 months later. Of course, this depends a lot on how
quickly you think you could get things done under optimal time.

In practice however, I rarely use this method since my estimates seem
to be way too large. If you keep track of how long projects go for
compared to how long you estimated they would go for, you should be
able to learn from bad estimates and become more accurate.

Project 1: Start with how long you think it will take (in days) in an
ideal world, multiply by 4, add 2 days. Now divide out into weeks,
ignoring the weekends and holiday.

At completion of project 1, determine if the multiplier was correct.
There is a good chance that you will need to adjust it to be between 3
(steller folks, keep them) and 5.

I disagree with the comment of pass through your employee ideas. As a
project manager, you really should protect them from themselves. It is
a good idea to ask, but add at least 20% to their estimates (or use
the above, whichever is longer).

Good luck!