Jochen Kalmbach's answer might work in older versions of Visual Studio, but it didn't work for me in Visual Studio 2013. However, the small RegEx shortcut buttons to the right of the Find/Replace input boxes helped a lot:

In Find, select the ":q Quoted string" option.
In Replace, select the "$1 Substitute the substring matched by captured group number 1", and then surround $1 with _T().
Final Output
Find:
((\".+?\")|('.+?'))
Replace:
_T($1)
Note that the $1 represents the RegEx expression group enclosed in the outermost parentheses.
Here's another example:
Requirement
Find:
Converter.toCustomObject($find("Anything"));
Replace (different Converter method and add parameter after $find() parameter):
Converter.toDifferentObject($find("Anything"), true);
Solution
Find (use RegEx in Find options):
Converter\.toCustomObject\((\$find\(.*)\);
Replace:
Converter.toDifferentObject($1, true);
Notice that the Replace value doesn't need to escape special characters, though you can apply some RegEx, e.g. to add a Line Break after the output, you can use this for Replace:
Converter.toDifferentObject($1, true);\r\n