I was wondering the same thing as Dapanz. However, as long as you're asking you might want to check out this place.
Las Orquideas Inn
http://www.orquideasinn.com/ is not exactly in Atenas but it's pretty close. Its about 5km WEST of Alajuela. Its also only 10 minutes from the airport (& on the side with less traffic), which is what first brought it to my attention as a possible place to stay if I was leaving on an early morning flight back to the states.
The room descriptions and pics seem very nice. But what the place is famous for is 2 things. The have a funky little bar packed with Marilyn Monroe Paraphanalia. And they claim to have the best breakfast buffet in Costa Rica. Numerous reviews from such sites as Frommers, Lonely Planet and the Moon Guidebook seem to bear that this is a nice place. I did find one semi-bad review that suggested you not opt for the cheapest $55/nt roadside rooms due to noise from passing trucks (other rms range from $65-130). The garden view and mountain view rooms got all good reviews. I'm not sure about chica-friendliness, but I do know they don't allow K*ds under 10 for whatever thats worth)
While I'm at it here are few other possibilities. One is El Cafetal B&B
http://www.cafetal.com($75/nt + up). It is about 5km north of Atenas and the home of Mirador del Cafetal, which I believe has been mentioned in other threads. The other two are
http://www.vistaatenas.com and
http://www.hotelcolinasdelsol.com (each about $45/nt)