Whoa there! You do not know what you are asking here!
Getting a local copy is a trivial operation, but the concept of a "local database" is not something MySql knows about - you would need a MySql installation on each and every machine it is to run on.
Worse, you will then have to deal with Replication which is it's own good thick book subject all on it's own! The problem is that you can't just go "add a record" to ten local databases, and expect them all to be sorted out for you when you return them to base and stuff the data back into the main database - you have to be very careful, or you will lose data, or correlate a customer with the wrong order. It is certainly possible to do, and it works pretty well, but it isn't just "get a copy and run away".
Time to do a good amount of reading! Start here: http://dev.mysql.com/doc/refman/5.0/en/replication.html
] and then branch out via Google.