There are a number of methods you may use to obtain a copy of Kubuntu, all of which are described on the Kubuntu Web site download page.
The first method is to download an ISO image from a mirror server near you and make an CD to install Kubuntu. Two types of CDs are available:
Desktop CD - the desktop CD allows you to try Kubuntu without changing your computer at all, and at your option to install it permanently later. This type of CD is what most people will want to use.
Text-mode install CD - the text-mode install CD allows you to perform certain specialist installations of Kubuntu. This type of CD is intended for cases such as creating pre-configured OEM systems or setting up automated deployments; it can also be used as a package source for upgrading older installations.
If you don't have a CD burner or you have limited or expensive bandwidth, we can send you pressed copies of the "Desktop CD" free of charge. You may request CDs via Shipit, the Ubuntu CD Distribution System.
Ordered CDs may take several weeks to leave the warehouse before being shipped, and can take several months to arrive.
Another method of obtaining Kubuntu is to join a local Linux Users Group (LUG) and ask if somebody with Kubuntu would mind making a Kubuntu CD for you. Normally, you will have to replace the CDs used for the duplication and reimburse any postage or delivery costs.
If you do not know of an LUG near you, a list can be found at Linux Users Groups Worldwide.