Hi,
Can someone tell me how I get more settlers to a port? seeing as the event log keeps saying that the port/town needs more settlers I assume there's something I can do about it.

It's been so long since I played that game, but if I remember correctly, settlers arrived via transport convoys.

Settlers usually arrive at Governor and Viceroy Towns. The game considers them "Imports", and usually arrive with the same frequency.
Because the game makes you start on one of these towns, you can rest assured that at some point settlers will arrive to your hometown.

It should also be added that each settler takes up 1 cargo space on your ship, and if you unload settlers in a town that needs workers, each settler will pay you 100 gold for the fare.

Settlers are also people. Any port experiencing a negative event that causes any sane person to want to leave, such as a recession or a war, will also generate Settlers. The population of the port will also go down as a result.