Domine name registrar discounts?

Hi,

I’m new to blogging. In fact, I haven’t even registered a domain name yet. I’m interested in WP.org for the flexibility, support, and great reviews it gets. But I’m confused right now by all the packages that you can buy from the domain name registrar – email, shipping cart, monetization. Purchasing one of these products reduces the domain name charge. So I’m wondering if I would be likely to NEED to purchase any of these things in the future, or if I’ll be able to get everything done with WP. I am interested in making money and maybe even selling items eventually. Of course, I want to go with the best registrar for my needs.

Thanks!