Goo Gone Sticker lifter, brilliant stuff. Just follow instructions.http://www.amazon.co.uk/Goo-Gone-Sticker-Lifter-55g/dp/B003A17DHO
there are a number of solutions. IPA (iso propyl alocohol) as stated above is good. Petrol works ok too. Autosmart TARDIS (Tar and glue remover) and Autoglym tar and glue remover works too.You can buy a "caramel wheel"/"toffee wheel" which attaches to a drill to remove it too - this is what bodyshops use but if you go at it too heavily it can burn the paint, so take care!heat is generally a good solution. If there is still anything mounted to the double sided tape, you can take the majority off with Dental floss! you can see a guide to "de-badging" a car here which includes a lot of the same steps involved:http://www.detailingnation.com/showthread.php?7827I am not registered to this site and so cant see the thread.
Had a few on the wheels of my old fireblade, touched them in with a black magic marker pen. No one ever noticed!