I'm mainly a server side developer. I'm not a designer, even if I understand web layouts, grids, CSS, typography, valid markup, etc. and I'm able to do some graphic work too (almost). It just takes a lot of time and the result is not always beautiful.

I know there are tons of website templates sites out there, and I'd like to use their designs as a starting point for my customers' works, giving them the possibility to choose the design they like more.

I'd just prefer to show the templates catalog to customers from within my site, fetching templates info (screenshots, description, etc) from a remote server using an API. TemplateMonster.com provides, or provided, such API. But the service responds with "Unauthorized usage".

Are there other sites offering this kind of retrieval service?