Los Angeles-based AudioMicro, the online marketplace for stock music and sound effects headed by Ryan Born, is announcing today that it has added another 20,000 tracks to its marketplace. The firm--which is allows users to access music clips and sound effects for incorporation into web videos, short films, applications, and other projects--said the production music tracks were prviously only available to broadcast television and feature film producers. AudioMicro's marketplace is similar to the stock photography market, allowing producers to download tracks and clips for as little as $2 each.