Can anyone please advise me as to where I can obtain a detailed map of lagoa/Carvoeiro. Hopefully something on the lines of a Uk ordenance survey or near to it

Check out:
http://www.igeoe.pt/concelhos/WebForm1.aspx
You can order online.
This is the Instituto Geográfico de Exército, the Army Sevices. Each chart about 5 euros, scale 1/25000. The Lagoa/Carvoeiro should be number 604 chart, but I am afraid the paper version is an old edition (seventies). You may buy one more up-to-date digital vector chart from the same site of 2002 (flight)/2004 (ground).
Paramonte

I remember this question was asked some while ago - have a look at
viewtopic.php?t=3544&highlight=map
G