Can someone advise where I can get nice sales page or landing page to promote my products online. I want a customized one and that can also allow diff payment options for buyers
Check those ones, you can easily customize them: http://themeforest.net/item/justlanded-wordpress-landing-page/3804089 http://themeforest.net/item/leadinjection-landing-page-theme/14532230
Are you using wordpress? You can create your own using a page builder plugin. I personally use profit builder plugin and it has some nice templates to choose from. You can also check other page builders as well
In case you are not using wordpress, you can get nice landing pages and much more from Kickofflabs. Also since you are looking for some customized landing pages I assume that you have an autoresponder service, right? some of the autoresponders services out there such as Getresponse include landing pages if I'm not mistaken.