I've spent some time in a detail section of a bmw forum where detailing pros post up and share.
1. Get a variable speed Porter Cable Random Orbit polisher and a set of pads (can't think of the pad names but they come for different applications.)
2. clay (you can get a clay kit at any wally world etc.)
3. Polish (if you dont want to spend $$ but want something good can't go wrong with Meguiars.)
Meguiars 105 and 205 Combo
1 polisher is coarser, than the other, start with the coarser one first, to remove oxidized paint etc. than the finer polish to remove swirls etc.
4. Seal with your favorite sealant or carnuba wax.
It is a process but you will be amazed how much better the car's paint looks after wards. Repeat after 6 months. (I don't on the cruiser bec it is pointless if you run trails (can't avoid pin striping)
The Porter Cable is the most important tool here if you want to get good results.
EDIT
Interior: Woolite 1 parts woolite 10 parts water....srub anything inside that you want with it.
Leather: Leatherique Rejuvenator Oil nothing else will match its effectiveness at rejuvinating and softening up old leather.