Ibis Karlin I stayed here 2 years ago nice enough snap a bit dear and about a 20 minute walk into the centre http://www.pragueholiday.cz/ibiskarlin.php Oh BTW Don't bother going /poo
Hotel Junior Prague. Stayed there for a weekend in 2006. Was good, but basic. Fairly cheap and all right if its a stag do! http://www.euroagentur.com/en/ea-hostel-junior-praha/booking
Book with these: http://www.travel.cz/ Office in city centre, stag friendly, will arrange transfers on request too. Offer cheap central accommodation, furnished apartments we used were ace - just off Wenceslas Sq., (and with the added advantage of no staff to worry about), but I'm sure the hotel deals they do are OK too.