From Amsterdam to Delft and Edam, take the train. Simply purchase your tickets at the station on the day of your journey; advance reservations aren't possible. Same deal with train tickets to/from Bruges. Travel time is 3 hours 47 min. with a change in Antwerp.

Check schedules here:

http://www.nshispeed.nl/en

Thank you! Do we have to take a high speed to Bruges? Is there anything cheaper?

If you want to take the high-speed Thalys train to Antwerp, it's an option....but in order to get cheap fares you have to book well in advance, and you're locked into a specific departure.
It's simpler and more flexible to use the regular inter-city trains (no advance reservation necessary or possible); even though travel time is a bit longer. The fare is about 35 euros.

Between Amsterdam and Antwerpen (where you make your change to Brugge), you have three choices by rail. The most expensive, but fastest choice is Thalys. Next, is an IC (intercity) train, and slowest, for the same price as the IC, would be a series of IR trains (inter-regional), with changes in Roosendaal and Antwerpen, but there's not point in doing this option. You can take either an IC or IR route between Antwerpen and Brugge, but the price is the same. One ticket will cover the cost of both legs of the trip, no matter which option you take.

If you want to see a castle (and several impressive cathedrals), just take a quick trip to Ghent from Brugge.

PS- In my opinion, Rick Steves' Benelux book is pretty weak. Supplement your research with more comprehensive sources (Eyewitness Guide, Lonely Planet, etc.).

I love France but don't see it working with your itinerary, unless you can arrange to fly home from Paris.

We made that run last Fall using the local trains. Take an extra hour or so in Antwerp between trains. The train station itself is interesting and it sits on a plaza. On the left side as you exit the station there is an ice cream/choc shop. Worth a stop. We went from Bruges to Delft (overnight) and The Hague. There is more than enough to do in Bruges. Rent bikes and ride the canals through the country side. We bought our tickets the day before for all of our trips.

You can purchase the A Frank ticket on line and should probably do so. You pick a time and by pass the long line to get in. The museum pass can be bought at the first museum that you visit. And it is a good value.

wow, this is all so very helpful! Thank you!

While in Bruges, take the train up to Ostende. It only takes about 15 minutes and costs around 3 euro. There, you can see the North Sea, take a walk on the beach or the mile long promenade, and see some of the old gun emplacements from WW2.

I liked Antwerp a lot, it might need more than just an hour or two.

If you want to spend a few hours nosing around Antwerpen, realize that with your Amsterdam to Brugge ticket, you are not limited to taking any particular train for the Antwerpen to Brugge leg. Trains leave in that direction virtually every half hour. So, if you want to explore for a few hours, just secure your luggage in the station (one of the biggest in Europe) and come back later in the day.

Antwerpen isn't the most immediately pretty city in Belgium. But it's well worth a look, in my opinion. Others will argue, but I find the Grote Markt here more amazing than Brussels' version (better known as the Grand Place). It's soaring late gothic, Reubens adorned cathedral is one of the most under-rated in Europe. I also enjoyed the sailor's museum, which is set in an old castle overlooking the Scheldt river.