When did Gollum find the fellowship?

[midgetman]

When did Gollum start "Stocking" the Fellowship of the ring?

[Manwe Sulimo]

You mean "stalking", right?

Gollum was trapped in Moria (near Westgate) when the Fellowship fled the Watcher. After that, he followed them through the caverns, into Lórien, and down Anduin.