Where Should I Go to Get My Website Designed and Optimized?

I started my own business a while back, and it seems to be taking off a bit. I would like to get a good website so that I can expand even more and get orders from all around the country rather than just from local customers that have heard about me through my ads and word of mouth. Can anyone tell me which Indianapolis SEO company I should use in order to get the best design and optimization for my website? Do I need to use separate companies for design and optimization or can the same company do both? I want to get this up and running as soon as possible.