Rajeev, someone can help you with your story, but it would be a huge mistake to think you can completely outsource it to them. They need to understand your business, what pain it solves, who has the pain, how it's differentiated, etc. They need to help you bridge the leap of faith that an investor must make - but in the end YOU must own the story because whether you tell it with your deck, your 1-pager, in an elevator in 30 seconds, or wherever, it must be the same story every time.
With respect to visual design, look at other decks on the web and do it yourself. You make something look too professional and it shows you burned money (that presumably you don't have to burn) on a friggin deck! Investors want you using money wisely.