A product worth mentioning for hand polishing IMHO, for paints that are a little harder and need a wee bit more cut than something like ScratchX has to offer, is Menzerna PO91L Intensive Polish... Not the ceramiclear version, but the older style version. This has a very brittle abrasive in it, too much pressure by machine will shatter them effectively and ruin the cut. This makes it ideal for use by hand, as you can break the abrasive down pretty easily while still getting good cut.
Key to hand polishing is time - lots and lots of time! I wouldn't recommend doing the whole car in one hit. Rather, do a panel a day - in the evening as a chill out. That way you can devote a lot of time to getting it right without getting stressed about rushing to finish - it takes a long time to break polishes down by hand, and repeated applications may well be needed especially on harder paints.
