For me, the Safari extension Sogudi is indispensable.
The author describes it: Configure your own shortcuts to search or visit your favorite sites using just a few simple keystrokes in Safari
Unfortunately it doesn’t work (yet) with Safari 3.
This is a simple AppleScript replacement using your original SogudiShortcuts.plist file in the Application Support folder
set pListpath to (path to application support from user domain as text) & "SogudiShortcuts.plist"
tell application "System Events" to set {searchShortcut, searchURL} to {name, value} of property list items of contents of property list file pListpath
set searchString to text returned of (display dialog "Enter a search string:" default answer "" with title "Search")
set {TID, text item delimiters} to {text item delimiters, space}
set {cmd, arg} to {text item 1, text items 2 thru -1} of searchString
if (count arg) > 1 then
set text item delimiters to "%20"
set arg to arg as text
end if
set text item delimiters to TID
repeat with i from 1 to count searchShortcut
if item i of searchShortcut is cmd then
set foundURL to item i of searchURL
set {TID, text item delimiters} to {text item delimiters, "@@@"}
set foundURL to text items of foundURL
set text item delimiters to arg
set foundURL to foundURL as text
set text item delimiters to TID
exit repeat
end if
end repeat
activate application "Safari"
tell application "System Events" to tell process "Safari" to keystroke "t" using command down
tell application "Safari" to set URL of current tab of window 1 to foundURL