I own a website and I want to add services to it and sell some local products to our provincemates abroad, but i don't know how to do about with that "shopping cart" and how to do about that accepting credit cards or payments on line. can somebody help me? can somebody show me how to do it step by step? i need your honest guidance & advice! thank you..

Here is a nice resource to check out
http://www.onlineorders.net/

To the left of the page you will find a complete listing of merchant account providers.

Good Luck