Create Subdomains on the fly with .htaccess (PHP)

I am looking to create a system which on signup will create a subdomain on my website for the users account area.

Wildcards in a hosts file

I want to setup my local development machine so that any requests for *.local are redirected to localhost . The idea is that as I develop multiple sites, I can just add vhosts to Apache called site1.local , site2.local etc, and have them all resolve to localhost , while Apache serves a different site accordingly.

How do I CURL www.google.com - it keeps redirecting me to .co.uk

I am using CURL to check for the existence of a URL (HEAD request) but when I test it with www.google.com , it redirects me to www.google.co.uk - probably because my server is UK-based.