Below are some sources of responsive design template that you can use. Most are free.
- HTML5up.net – free HTML5 responsive template (not boostrap)
- shapebootstrap – free bootstrap template. need to register and login
- freshdesignweb – 70+ free boostrap template. compilation from various sites
- boostrapzero – free bootstrap templates. one-page, admin
- wrapbootstrap – paid bs templates. many categories – business, resume, admin, landing, portfolio. avg price $10
- themeforest – paid templates – bs, wordpress etc. more than 21k templates available.
- blacktie – compilation of templates
- compilation of free admin bootstrap template