That is an excellent care sheet.
As far as enclosures go, it depends on the size ... as an adult, they need a size of at least twice their body length by 1x their body length ... so a 4 foot lizard would need an enclosure 8 'by 4 '.
As babies, the same rule more or less applies, but the requirement is much easier to meet. I keep my 18 "baby in a 2.5x1.5 (I think it's a 64 quart) Sterilite tub with holes in the top for heat and UVB lamps. I lay a 10 gallon screen top over the holes and put them lamps on that.
As for substrate, I like organic potting soil. Tegus love to dig, and will be very stressed if they can't.
For accurate advice from extremely experienced keepers I would recommend you visit www.rfuk.co.uk a reptile related forum. There are many knowledgeable people there who will offer you sound advice.
I recommend you have a read through this very good care sheet:
http://www.reptileforums.com/forums/show ... pets question and answers,www.5d2d.com
This chap keeps an adult in a 8ft x 8ft enclosure.
