My background is as follow:

Since after graduating from college with a degree in Business
Administration two years ago, I've worked for two companies - a CPA
firm (about 1.5 years) and an optometry office (9 months).  I worked
in a small CPA firm as a bookkeeper and currently working at an
optometry office doing something related to marketing - writting up ad
for newspaper, coordinate trunk shows for the stores, and some
clerical work.  I have a strong sense in accounting as I keep track my
daily expense on Quicken as well as very good organizing skill in my
opinion.  I would like to ask that with my background, what kind of
business I can start with a saving of $20,000.  Currently I am making
$2,500 gross income per month and my fixed expenses (rent, gasoline,
insurance, telephone, meal & entertainment) is about $1,500 so I can
save about $1,000 per month.  My objective in life is that I do not
want to be an employee for a long time as I got tired for the 9-6
work.  I want to start my own business.  I can speak fluent Engish and
Chinese.  I have thought about selling things on ebay, getting an real
estate broker license, writing another resume for another job (which I
don't want the most), or...  Please let me know your suggestion of
what kind of business I can start (and how) while I can afford my
monthly fixed expense.  Currently I am 24 years old with no credit
card and auto loan.

Might I suggest a complementary approach to help you decide what's
best?  If I were you, I'd be thinking about what I would love to do.
So... what brings you joy? What are your passions? Are they things you
can convert into an opportunity to make a living?  Begin with the end
in mind, then establish the plan to get there.

Also, there may be things you can do for less than $20K. Remember that
as soon as you bridge to entrepreneurship full time, you will need to
continue payments on your monthly expenses like rent, food, etc. There
will be a period of time where you will be living off your savings in
order to get your business started (unless you start your business
part time while working full time or part time somewhere else.)

If you are looking to start a new business because you don't like the
LENGTH of time you have to work as an employee, i.e. from 9-6 or
approx 8 hrs a day, then owning your own business may not be an
answer.  Speaking from experience, it takes more hours per day to work
for yourself than it does to work for someone else. You've got all the
legal and administrative tasks on top of the actual job, so it's not
the easy way out.  If you simply are looking for the flexibility that
entrepreneurship offers, that comes after time... after you've worked
long hours to get things off the ground... :-)

hi natural00

the best way to start your own business is to start with a very
simple, focused idea. Think of a very specific costumer base and how
you can help them. Then start  thinking of the meaning of your product
or service. What I mean by meaning is the importance of your product
or service, the value or benefit that it would hold from your
costumer's perspective. Avoid thinking  in terms of profit, revenue or
money, infact, avoid thinking of any benefit to yourself other than
the satisfaction you will gain from your work in your business.
The point is to build a business with meaning to your costumers. If
your business has enough meaning to change the world, then investors
will want to invest, people would want to work for you, costumers will
buy from you and the money will come.
first, find an idea you can be passionate about, trully believe in it
and build a team of believers to help your startup. no one can tell
you what business you should start with your background information,
background has little to do with it.

Hi natural00-ga,

You are interested in an eBay business or other self-employed
business. I've found from a lifetime of self-employment that it can be
difficult at times, but is very rewarding. I've also helped others to
get started on their own home businesses, and the biggest mistake
others have made is to quit their job because they have a cushion of
$XX,XXX on hand.
My advice to you is to  find a job that you may not want permanently,
but at least doing something that you enjoy a little, and make sure
that it's a job that doesn't require extra long hours.
Then take some of your extra time and start working on creating your own business. 
EBay might be a good way to go. I had bought things on eBay for several years, 
but had no idea how to sell. I bought some ebooks on how to sell on eBay
 (http://tinyurl.com/4v8nu), spent a few days reading them, and within
a week I was selling on ebay.
I found that it takes about 2 or 3 months to learn the basic "tricks"
of selling, and that the secret of selling on eBay is finding the
right products, and figuring out a niche market that will be
interested in your products.
How you describe your auction makes all the difference. 
For example, I bought a colleciton of electronically deliverable
ebooks and software that others were having difficulty getting $2 for
on eBay, put a short extra description at the top and bottom of the
standard advertising for this product, and used a new fresh
description that didn't mention the old worn out title the others were
using to describe it, and had no difficulty selling it over and over
for $9.95, which by the way is pure profit. Take a look at my auctions
and you'll see this item most days: http://tinyurl.com/6bx6q.
In summary, eBay can work for you as a full time business, and it's
very enjoyable work, but don't expect to make it work in a couple of
months.
Give yourself at least 6 to 12 months with whatever you decide to do
to see if it's what you really want, and plan ahead financially so you
won't run out of money if it turns out to be the wrong career for you!
Be well and happy,
Marty