For me, thats a hard question because there are so many scanners on the market. Depending on what your plan of use would be, if its for professional or personal use, if you need bi-directional capabilities, etc. I personally use high-end tools in the field (diesel) but only have need for a basic scan tool for personal use. These things can get pricey so it depends on what you intend to use it for. Basic: Anything the autopart stores carry...Actron CP9580 Auto Scanner with CodeConnect OBD II, CAN and ABS. OTC 3111 w\ ABS.... and so on. I personally use a Code Scout 2500 and a Auto Xray AX7000 TechScan for my Tahoe, Contour, 3500 and Focus.
'I know where the 'zetec' kicks in....'