The standard keyboard shortcut for finding text in most applications is Ctrl+F. In Visual Studio, this kicks off a Quick Find in the current document.
Quick Find will pre-populate the find what text with whatever text is selected in the editor or the word that the cursor is currently on.
Additionally, this find and replace window is actually a tool window (not a dialog), meaning that you can dock it somewhere and type in the editor with it opened.
Technorati tags: VS2005Tip, VS2008Tip