NattyWP started in 2008 and produced free WordPress themes. They now sell several premium themes. You can buy themes individually or join their club for access to all themes. Support is provided via a helpdesk ticket system. The provide the more popular types of themes for WordPress which are magazine/news, business, portfolio and good old fashioned blogging themes. Their themes are licensed under the GPL. Developer packages are available if you need layered PSD files.
Premium WordPress theme sellers typically include support and upgrades with theme purchases. Visit NattyWP's website for complete details including the most up-to-date pricing.
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