Here is a care sheet i have written up. I have attached some pics of my setups for adults and little ones.
Housing
A large fish tank (1200(4') or more) or large plastic tub is ideal for raising youngsters.
Adults should be kept in a large enclosure either inside or outdoors. IMO 4x2m would be a suitable minimum for an adult, smaller would be ok but not desirable. You will need to make sure they can’t burrow out if kept outdoors. The enclosure should be well ventilated.
Cage Decoration
You need to provide plenty of hides and its best to give them something to tunnel in, clay soil is good. Having the basking lamp over the soil or hide will allow the monitor to sleep in a warm place. Rocks are good but you need to be extremely careful how they are positioned so that the goanna can’t be pinned or crushed. Bricks and besser blocks are great because they are flat so they can’t wedge under them and they also can hold a fair amount of heat. Other suitable hides include bark, hollow logs and boxes. Climbing branches are worth adding but not really needed. Rough or sharp edges should be avoided.
Heating
They should be provided a very hot basking site around 60C is good (yes that hot, think how hot the ground gets on a hot day...) Unless in a very cold area this basking heat should be enough alone, it is important to provide good hiding areas in the hot part of the cage if the whole enclosure is not kept warm. A heat cord or mat can be used to provide additional heating. If kept outdoors in a warm area with full sun additional heating may not be needed but in many cases a basking lamp may be needed for outdoor enclosures.
Water
Although they wouldn’t need to drink very often it’s a good idea to have a water dish just large enough for them to submerge in. Keep it at the cool end to keep the humidity down.
Feeding
I feed mine chicken, rodent, roo, beef, fish, various other meats, insects and spiders but they will eat most meaty foods and live invertebrates. I usually supplement chicken necks and plain meats with a multi vitamin or Wombaroo and prefer to make the bulk of the diet up of entire animals.
Captive Behaviour
They make great captives and generally don’t bite (unless they mistake you for food). They can become used to handling but they still seem to dislike it and like their own space (like all goannas IMO). A large specimen could cause serious damage so they must always be treated with caution. A 4kg+ goanna holding on and shaking its weight around would not be cool. Being tame doesn’t always stop it from biting with a feeding reaction(just like with a snake). Mine often charge at the door at feeding time jumping and biting at anything that might be food. They will sometimes try and crap on you (they have good aim too) if picked up when not used to handling. They will also hiss and whip you a bit and can also scratch either intentionally by digging their claws in or simply by struggling. If you treat them with respect and you will get along well.
Incubation
Eggs incubated at 29.5C hatched in 126 days and this is consistent with other data I have seen.
Links
http://mampam.50megs.com/monitors/advice.html
http://mampam.50megs.com/monitors/spenceri.html
http://www.monitor-lizards.net/speci.../spenceri.html