I would highly recommend the HP 3015 or the 3050 (I bought the first years ago for my parents -- testament to its ease of use -- and the 2nd recently for myself, the equivalent later model). You can probably find one used in good condition on craigslist or ebay locally for <$150.

They're cheap, solid, and don't cost a lot for toner. Add a mini print server from Netgear/Dlink/Linksys on the back and it's instantly networkable.

Note though that the current model (derived from these mentioned) is the M1319f MFP which I specifically avoided, because I understand (though I could be mistaken) they've taken out the PCL (?) chip to save money, so it relies on the computer to render the graphics -- ie. it cannot print as a common printer. But others please correct me if I'm wrong.