Why raise money at all? To deploy a web app all you really need is a virtual server like SliceHost, Linode, etc. This costs $20-40 per month and should have enough resources for a regular web app until you get really big (in which case you should have some revenue to help cover costs).
Watch Tom Preston-Werner's (the founder of GitHub) speech at Start-up School for inspiration: http://www.justin.tv/startupschool/b/272178966