Which spokes should I get for an Expresso Coaster Brake with a Velocity Deep V 700c I'm working on my first coaster project with an old 700c frame which I want to make really clean using an Espresso Coaster Hub.

http://www.espressowheels.com/griptape.html

Rear black coaster brake hub with 32 holes. Includes 16T chrome sprocket, chainstay fittings, nuts and bolts. Hub width: 120mm, 
axle diameter 3/18".

I got the Hub from a friend and I want to make a nice rear wheel with a White Velocity Deep V 700c
http://www.velocityusa.com/product/rims/deep-v-622

I don't have experience building custom wheels, so I was wondering if you know which length spokes I should get to have it built. 
I emailed espresso but haven't heard back yet. I live in the Hague in the Netherlands so any recommendations as to where I should get the wheel built and how much I should pay would be great.

Someone recommended I just take the rim and hub to the bike shop and have them pick the spokes and make it rightaway. Is that a better option?
Since you live in the Hague: There is a good chance these guys have experience with espressowheels. For a more general answer: just go to a bike shop with the hub and rim and they'll be able to help you.