looking for a city center B & B or the like. Small and inexpensive. Traveling alone. No need to impress.
For a unique experience try a botel. We stayed on Botel Christina (http://www.intersail.nl/group-travels.htm), but there are a few others in the harbor right in front of central station. I believe you can find listings for them on hostelworld.com or by googling botel and Amsterdam.
John... Amsterdam is very expensive. That being said we like the Hotel Fita... check out their website. Very very nice for the price.
Hotel Orlando worked out great for me
Hotel Mercure (not sure of spelling anymore, sorry), the downtown one, not the airport one.
Walking distance to many things, very close to tram stops and the green carousel restaurant.
Hotel is clean, quiet, has a good but pricey breakfast, friendly staff. We were there 7 nights.