There are two types of kannada fonts ASCII and Unicode. There are lot of kannada fonts available in ASCII and Unicode format. Some of them are Proprietary and some of the kannada .fonts are released using GNU/GPL License.
Kannada Fonts ASCII
Lot of Kannada ASCII fonts are available. Most of the fonts are Proprietary. Each kannada font use custom kannada keyboard layouts. To type in kannada .a user need to learn these layouts also. To read various kannada text an average user need to install all these kannada fonts.
Kannada Unicode Fonts
Most of the unicode kannada fonts are released under GPL license. You can download them free of cost and use them. The Unicode fonts are presented with common keyboard layout called Inscript. Some of the kannada fonts are listed below.
Download Kannada Fonts for Windows and Linux
Open Type Unicode Compatable Kannada fonts for Windows and Linux.
Download Akshar Unicode Font (Akshar.ttf)
Source: Free download from Kamban Software.
Stats: Version 0.07 December 23, 2004 has 1,751 glyphs and no kerning pairs
Support: Devanagari, Kannada, Latin, Malayalam, Tamil, Kannada
OpenType Layout Tables: Devanagari, Kannada, Malayalam (old style), Sinhala, Tamil, Kannada
Download Kannada Fonts from Kannada Software