The question seems to imply the need for a single document uploaded to a lib, then accessible from many different pages/sites. In WSS 2 the mentality behind this solution was very OS folder-like: create multiple copies. WSS 3 has added an additional dimension, Content Query Web Part solves the need for storing multiple copies of a document. It allows the viewing of content across site and page boundaries, but OOTB only in a single site collection.
But that doesn't help you in WSS 2. If a 3rd party solution is acceptable, try the Bamboo Solutions List Rollup web part. Functions a lot like the CQWB, allowing views of list/library items across site boundaries, but it also works across Site Collection and even Application boundaries (Areas in SPS). It supports both WSS 2 and WSS 3. Trial download is free, works for 2 weeks.