You need to look at MySQL's LIMIT command.
Taken from the MySQL manual:
Here is an example of how to use Limit:
The first example will limit the result to the first 10 items.
SELECT name FROM customers LIMIT 10
This example will limit the result to 10 rows, starting with row 5.
SELECT name FROM customers LIMIT 5 , 10
If you only use one parameter, it will be the number of rows to return, if you use two parameters, it will be where to start, and then the number to return.