well thanks to ALL of you for all of your comments; very helpful and imformative. I have read loads of info on the subject.........seems like it is quite a professional art - one site actually advised NOT to undertake the 'detailing' task with a power polisher, (unless trained) or if you hadnt done it before, or had never used a power polisher.................................hmmmmm...think i'll stick to good old elbow grease...otherwise i could be driving round in a blotchy miggy !!!!! lol

PS - i would appreciate any recomendations for a GOOD polish and a good wax - TIA

You can buy their stuff in Halfrauds.
They do a matching clay bar kit too. Clay bar will really help you. Keep it lubricated, but the way it works is a bit like using a big lump of blue tack to clean biscuit crumbs off a carpet.
The clay bar pulls all the contaminants (such as brake dust) out of the surface of the paint and leaves it glass smooth then allowing you to wash, hand polish and wax properly.
I would disagree slightly with the advice that "using a clay bar is as good as polishing", they are different and a clay bar is preparation for polishing. They are both as good as each other, and you need to do them both; clay bar first followed by polishing to do a professional job. The clay bar ensures that you are not polishing contaminants into the paint.
Another good thing to try to get hold of is some industrial strength traffic film remover ("TFR" to those in the trade). This stuff cuts through road film such as tar spots, tree sap, insect guts like nothing else and really gives you a good clean foundation. I'd do this bit 1st, then wash, then clay bar, then wash again then polish, then rinse, then wax.
BOTTOM LINE:
The hard and really worthwhile bit is the foundation (i.e. get it very, very clean and very very smooth) and the rest falls into place.
You can give a fair or reasonable clean and then wax a car to your heart's content, but it will never look as shiny and smooth as a car which has been cleaned properly 1st.
Those links to the detailing world pages are really it all in a nutshell.