If you are only printing 20 sheets a day, you probably don't want the bigger (better) models. I have a 3 year old Brother HL-1040, and it is very reliable. You can get the current model (1340? 1440?) easily for less than $300. Toner cartidges are pretty cheap ($30-40), and long-lasting. I'm sure HP and Canon have similar 'low-end' models.
Reviews can be found at Tom's or ZDnet
Check prices at Pricewatch
Also check ebay. I bought a $4000 HP Color LaserJet 4000DN for $600 and it works perfectly. Spent more on toner and drums than on the printer.