I'd recommend The FIrm Body Sculpring Basics also known as Volume 1 taught by Susan Harris. It is VERY 80's dress, hair, makeup and the music was instrumental and done to the fith the workout after it was filemed I belive. But it only requires dumbells and a towel (or yoga strap or belt or bathrobe belt can be used.)
I'd also recommend the Volume 2 that follwed it taught by Janet Jones Gretsky (sp?) but it is only available thru ebay of other forum swaps right now.
These are very tough and can be done from beginner to advance levels with just dumbells & the towels/strap used for stretching.
A more current series is from the same creators called Fitprime with is more stregnth based, and Kickbutt which is more cardio based. These require, dumbells, stool, towel/strap, yoga brick(substitute with a pillow) and dowel, which they show substituions for as a mop or swiffer or broom. This is only used for help while trying some of the balancing moves and a couple of cardio tunes.
More info on Fitprimes and preview clips can be found at
http://www.whfn.com/fitprime.php and the Kickbutt info can be found here
http://www.whfn.com/kickbutt.php
All range from 40-60 minutes and are great workouts that really involve the core.