If you plan to do business online and take payments for your services or products then you need an ecommerce website. There are a few options available. I would either customise and tailor a content management system to your needs which would include a catalogue and shopping basket, or I would write a tailor-made ecommerce application for you. When receiving payments you can either use a payment gateway such as PayPal or World Pay or use a more complex system which is directly connected with your bank, such as Protx. With Protx I can give you much more control over your payments, the downside is that you must get an internet merchant account from your bank. PayPal is a much easier method and is very effective for many businesses.