Where can I get some information about online travel agencies?

I'm doing some business research on online travel portals like Travelocity, Orbitz, Hotwire, etc... and would like to know where I can find some non-trivial information about these agencies like: how did they get started, how did the business take off, backgrounds of entrepreneurs etc... from sources other than Wikipedia...

Thanks in advance

Here's one for example on the link below about travelocity.

When typing in Yahoo or one of the "other" seach engines don't forget to include exactly what you are looking for.

"Travelocity founded by" example. It will take you to other "news articles".

Some sites you can use their links "about us" which often gives their startup information.