I did the New York Marathon in 2011, 13 and 14.
I used the baggage option for all 3 of the runs.
The bag they provide now is less than half the size that you get for London.
I managed to get my track suit, t shirt, socks, a lightweight anorak and a couple of chocolate bars in it, it was full. I usually put another pair of trainers in to change into after a race but there was no room.
When I get to the start area I confirm where my baggage lorry is and get my bag onboard around an hour before the start (you have to be in your start coral 30 minutes before your start time anyway). You'll need a bin bag or something to keep you warm for that hour.
I always carry a small wallet with me on the run with my hotel room key, subway card and a bit of cash, just in case.
At the finish the lower your race number the further you have to walk to get to your baggage lorry. I've never had an issue with getting my bag back at the finish.
The exit is a fair old walk when using the baggage option. You exit Central Park to the North West and then have to walk back south towards Columbus Circle but the subway is reasonably accessible to get to anywhere in Manhatan.
As far as spectator support is concerned, the quietest part of the course, for me, was around 12 - 13 miles, going over the Queensboro Bridge into Manhattan. The runners are spread out by this time but no spectators are allowed on the Bridge. It can be quite quiet for a mile or so, however, once you're off the bridge and going north in Manhattan the crowd and the noise is amazing (London at Cutty Sark or going over Tower Bridge).
There are a few ways of getting into the marathon.
There's the ballot, good for age or international travel partner.
The ballot tends to open in January each you and is open for around a month. You are charged a handling fee whether you get in or not (this year it was around $11).
If you get in the cost of entry is around ??250. It is difficult to get in via the ballot (like entry into London).
For a Good For Age entry you have to have run a Marathon or Half Marathon in defined times depending on your age. For non New York Road Runner events there are only a limited number of places available via this route so if you can achieve a Good For Age time you would need to apply for one of these places as soon as entries open (again in January). The cost of entry is the same as entry via the ballot.
You could go for entry via an Internation Travel Partner (ITPs). For the UK there 2:09 Events and Sports Tours International (they're the 2 I know about in the UK).
I've done the New York Marathon twice via Sports Tours International.
With the ITPs you get guaranteed entry into the race but you must also purchase flight and accomodation or flight or accomodation from them as well as the race entry.
I have bought an entry and flight from them both times (arranged my own accomodation in New York).Cost wise using a ITP is probably the most expensive option but you get guaranteed entry. It can cost around ??300-400 more overall to do the marathon this way than by getting through the ballot or GFA entry (sort your own flight and accomodation out).
The only other way you could do the race is getting a place by running for a charity but I don't know much on this entry method.
I've done the race 3 times, doing it again this year. I use the midtown bus service from the New York Public Library. I find its good if staying around Times Square or Grand Central Station. The journey takes just over an hour and so out at Fork Wadsworth around 7 am (assumes 5:30 bus departure). Make sure you take warm clothing with you. Fort Wadsworth can be freezing in early November. Depending on which wave you start with you could be waiting at Fort Wadsworth for 2-3 hours.
There's free coffee, water and bagels at the start. I usually take something that I'm used to to eat while waiting at the start.
I go for the baggage option rather than poncho but it does mean there's a fair bit of walking to get your bag back at the finish. I just prefer to know I've got some warm dry clothes once I've finished. There's a subway station a few hundred yards southbound once you leave Central Park.
In previous years there's the chance to buy finisher t shirts etc and get you medal engraved the day after the race, at the finish line in Central Park. It opens early (7am) and it's best to get there early (it can get crowded).
There's usually 2 queues - medal engraving and merchandise. If you want to go into both areas get into the engraving queue. Once your medal is engraved you can go straight into the merchandise area. If you get in the merchandise queue you'll have to queue again for engraving.
I.hope this helps for people doing the run for the first time - enjoy the day, it's one that will stay in your memory for a very long time.
In previous years the results have been put on the Out And About website a few days after the event. The results are left on there for a while but I don't think they have previous years results - could try emailing the race organisers.