Some good premium themes are available here:
https://themeforest.net/popular_item/by_category?category=wordpress
Premium themes offer lots of options though often you still want to do some custom styling. The first row in that list are the most popular and we use a couple of those themes to develop customer websites. A premium theme is worth buying if you like more fancy features like content animation like fadeins and higher number of editable page elements using an interface. After GST and exchange rates cost is roughly AU$100 each.
Some good free themes are available here:
https://siteorigin.com/theme/
http://mythem.es/item-category/wordpress/free-items/
https://athemes.com/collections/free-wordpress-themes/
If you know how to do css styling then the free themes are a bit more viable unless you simply stay within the theme framework when building your site.
For the WordPress shopping cart we recommend https://woocommerce.com/ plugin. Its easy enough to install in the WordPress dashboard and its core features are free and usually enough to get a good ecommerce site going.
We can install a free SSL certificate for your site to keep your customers data secure.
Redirection of domains can be done easily if you have more than one domain for your website and there is no cost involved. We can help with that when you are ready.
We also offer web design services if you need help at any stage building your site.
Enjoy WordPress