You guys may be such successful traders. Can we share the tips to others? Start online biz, what do we need to prepare?
You don’t really need to prepare anything before starting an online business. A computer, a website, and a PayPal account to get paid. I spent $13 creating a site in 2004 that would generate over $2 million in sales since then – I didn’t register any kind of business, I didn’t have marketing lists, I didn’t buy any special software or join any “internet marketing systems” – I just built a site, put it online, and started advertising it in free forum marketplaces.
Have a specific kind of business in mind?
I think it’s worth mentioning Dan that in some countries (like the UK), if you are making money through a personal venture you need to notify the tax people that you are making money in that method… as it will determine how much tax you are legally required to pay (even if its advertising revenue, a Paypal payment system or something more sophisticated). Over here, all your collective income determines how much tax you need to pay, even if you earn money through eBaY you are legally required and obligated to declare it (especially if you’re going to be classifying yourself as self-employed in the sense of making money solo. 
software is the cheapest industry in the world to get into. All you need is a computer, a text editor and an idea. that costs next to nothing.
if you are not that flash with the programming, there are plenty of net tutorials, or books on amazon for $30.
im in the process of building an n-tiered web application to service over 1m users. so far i’ve spent under $1k… books, a few desktop machines as servers and some other sundries.