I think some people don't know how to add 'Buy Now' image button in the sales thread. Its even better to add Buy Now button rather than links. So, here how to add it.
Simply use the following piece of BB code:
Replace YOUR_PAYMENT_URL_GOES_HERE with your payment URL and BUTTON_IMAGE_URL_GOES_HERE with 'Buy Now' image URL.PHP Code:
[URL="YOUR_PAYMENT_URL_GOES_HERE"][IMG]BUTTON_IMAGE_URL_GOES_HERE[/IMG][/URL]
Thats it