Where can I find Investors for my new online internet start up Company?

I have just recently filed for a DBA, and I have just started writing 2 separate business plans, generally the same idea but different themes. I think this could make a lot of money , and the return would greatly outweight the costs. These websites would generate profit through online advertising and a select few services we would provide to the user, but in order to build these 2 individual websites, I would have to put forth about 100,000 dollars worth (rough estimate), which would include all start up costs and etcs. After I have finished with the business plans, I will be in pursuit of investors? Where should I look for them? How should I contact them? Should I contact any specific ones that are interested in the internet?

Thank You.
I forgot to Mention… I do have somewhat of an online setup of one of these ideas already running… this was going to be the original idea, and solely owned by me and my partner. I thought I was going to be able to handle this on my own, but apparently not. I need more money than I already have.