Google chrome and Firefox are both Internet browsers rather than search engines so switching probably wont affect how you find info on the net very much.
If you are using google as your search engine then you can still view results from the UK but you now need to enter the search criteria first, press seach and then on the left hand side there should be an option to select 'pages from the uk only'. I also preferred being able to select UK only before running the search (when the option used to be underneath the search box)