TextCrawler is a popular find and replace tool, which works across multiple files and supports regular expressions and batch scripting.
This program is Freeware and contains no adware or spyware of any kind!
Download TextCrawler 1.1.4 for Windows
TextCrawler is freeware, but any donations towards future development are gratefully received. If in the future a pay-for version of Textcrawler is released all contributors will receive a full licence!
TextCrawler 
Download TextCrawler 1.1.4 for Windows