if its just balck and white buy a laser. A toner cartridge might cost up to 50 quid for one but you should get between 5000 and 10000 copies from a cartridge. usually have some pretty good deals. I bough a samsumg laser a couple of months ago for a client, 20 pages per minute, 25 quid for a toner cartridge (not needed one yet), 100Mb ethernet as well as usb/parallel all for 99 quid.
Personally I wouldn\'t give an inkjet printer house room. I have an epson 5000 proofer and it costs a fortune to feed. Bought a colour laser printer, which cost 7000 quid but I\'ve had 4000 copies out of it so far and still tons of toner left