One other option is using a guide service. We have a good relationship with EMS Climbing school and EMS Adventures. The climbing school offers single day (http://www.emsclimb.com/mountaineering_washington.html) and overnight summit trips (http://www.emsclimb.com/mountaineering_obs.html). The adventure school did the same type of trips this past summer. Not sure if they will next summer but you an check their site as it gets closer at: http://www.emstrek.com/northeast.html. There are other guiding services out there that can take you up and down in a day. IME (http://www.ime-usa.com/imcs/index.html) is the other big one I know of. There are a few private guides as well. But, if doing it in the summer, you can do it in a day pending on what trails you choose. I did it four days in a row this past summer (partly for work and partly for fun). But at least you are starting off right and using the forums for advice. If you use the search function, you can probably find a lot of other threads with answers to your questions as well.
Staff Meteorologist/Night Observer, KMWN (Mt Washington Obs., NH)